Given the accumulation supply, the level of income or employed is established by the level of accumulation demand; the better the accumulation demand, the greater the level of income and also employment and vice versa.

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Keynes was no interested in the components determining the accumulation supply since he was involved with the brief run and also the existing abundant capacity. We will likewise not explain in information the determinants which de­termine the accumulation supply and will confine ourselves come explaining the factors of aggregate demand.

Aggregate demand consists of two parts—consumption demand and investment demand. In this post we will explain the consumption demand and also the components on which the depends and how it changes over a period of time. Consumption demand relies upon the level the income and also the propensity to consume. Us shall explain below the meaning of the consumption role and the factors on which the depends.

The principle of usage Function:

As the demand for a an excellent depends ~ above its price, an in similar way consumption the a neighborhood depends top top the level of income. In various other words, consumption is a function of income. The con­sumption duty relates the quantity of consumption to the level the income. As soon as the revenue of a neighborhood rises, consumption additionally rises.


How much intake rises in solution to a provided increase in earnings depends ~ above the marginal propensity come consume. It have to be borne in mind the the consumption role is the whole schedule which describes the quantities of consumption at assorted levels of income.

We give listed below such a schedule of usage function:

Table 6.1. Linear usage Function:


Consumption function should be very closely distinguished indigenous the quantity of consumption. Through consumption role is supposed the entirety schedule which shows intake at miscellaneous levels the income, whereas quantity of consumption method the amount spend at a particular level that income. The schedule described above reflects the consumption duty of a com­munity i.e., it indicates just how the consumption changes in solution to the adjust in income.


In the above schedule it will certainly be checked out that in ~ the level of income equal to Rs. 1200 crores, the quantity of intake is Rs. 900 crores. As the national earnings increases to Rs. 1500 crores, the usage rises to Rs. 1125 crores. Thus, with a given intake function, lot of usage is various at various levels of income.

The over schedule that consumption role reveals an essential fact the when earnings rises, consumption likewise rises however not as much as the income. This fact around consumption function was emphasised by Keynes, who first of all evolved the concept of intake function. The reason why usage rises less than income is that a component of the increment in income is saved.

Therefore, we watch that when revenue increases indigenous Rs. 1000 crores to Rs. 1100 crores, the amount of consumption rises indigenous Rs. 750 main point to 825 crores. Thus, v the rise in revenue by Rs. 100 crores, consumption rises by Rs. 75 crores; the staying Rs. 25 crores are saved. Similarly, when earnings rises indigenous Rs. 1100 crores to Rs. 1200 crores, the lot of usage increases native Rs. 825 crores to Rs. 900 crores.


Here also, together a result of boost in earnings by Rs. 100, the amount of consumption has risen by Rs. 75 crores and the continuing to be Rs. 25 crores has actually been saved. The same applies to further increases in income and consumption. We shall see later on that Keynes based his theory of multiplier on the proposition that usage increases less than income and also this concept of multiplier occupies an essential place in macroeconomics.

Consumption demand depends ~ above income and propensity come consume. Propensity come con­sume relies on various determinants such as price level, interest rate, share of wealth and also several subjective factors. Because Keynes was concerned with short-run consumption function he assumed price level, interest rate, share of riches etc. Constant in his theory of consumption. Therefore with these components being assumed continuous in the short run, Keynesian consumption duty considers consumption as a function of income. Therefore

C= f(Y)

In a certain form, Keynesian role can be composed as:


C = a + f(Y)

where a and b room constants. If a is intercept term of the consumption function, b stands for the steep of the consumption duty and as such represents marginal propensity come consume.

Keynesian consumption duty has been portrayed by CC’ curve in Fig. 6.1 in which follow me the X-axis national revenue is measured and also along the Y-axis the lot of consumption is measured. In this figure, a heat OZ do 45° angle through the X-axis, has been drawn. Because line OZ provides 45° angle through the X-axis every suggest on that is equidistant indigenous both the X-axis and also Y-axis.

Therefore, if consumption role curve corresponds with 45° line OZ the would imply that the lot of consumption is equal to the earnings at every level the income. In this case, through the rise in income, usage would likewise increase by the very same amount.


As has actually been claimed above, in really practice intake increases much less than the rise in income. Therefore, in actual exercise the curve illustrating the consumption function will deviate native the 45° line. If we represent the above consumption schedule through a curve, we would get the propensity come consume curve such together CC in Fig. 6.1.

It is obvious from this figure that the consumption duty curve CC’ deviates from the 45° line OZ. At reduced levels the income, the consumption role curve CC lies above the OZ line, signifying that at these reduced levels of income usage is higher than the income.

It is so because at reduced levels that income, a nation may draw upon its built up savings to maintain its intake standard or it might borrow from others. As income increases, consumption likewise increases and also at the earnings level OY0, usage is equal to income.


Beyond this, v the boost in income, intake increases however less than the rise in income and also therefore, consumption duty curve CC lies listed below the 45° heat OZ beyond Y0. An im­portant suggest to be provided here is that beyond the level of earnings OY0, the gap in between con­sumption and income is widening. The difference in between consumption and also income to represent savings. Therefore, with the rise in income, conserving gap also widens and as we shall view later, this has a significant implication in macroeconomics.


It is beneficial to point out here that as soon as the consumption duty of a ar changes, the totality consumption role curve transforms or shifts. As soon as propensity come con­sume increases, it way that at miscellaneous levels the income an ext is consumed than before.

Therefore, together a result of increase in propensity to consume that the community, the totality consumption role curve shifts upward as has actually been shown by the upper curve C’C’ in Fig. 6.2. ~ above the contrary, when the propensity to consume the the ar decreases, the totality consumption function curve shifts downward signifying that at various levels the in­come, less is consumed 보다 before.

Average and also Marginal Propensity come Consume:

There space two important ideas of propensity to consume, the one being median pro­pensity come consume and the other marginal propensity to consume. They need to be very closely distinguished, for they space equal in some cases however different in others. Think about Table 6.1, wherein we have calculated the average and also marginal propensity come consume in columns 3 and also 4. As viewed above, consumption transforms as income changes.

Now, just how much consumption alters in solution to a given change in earnings depends upon the average and marginal propensity come consume. Thus, propensity to consume that a ar can be well-known by the average and marginal propensity to consume. Mean propensity to consume is the proportion of the quantity of usage to complete income. Therefore, typical propensity to consume is calculate by dividing the lot of usage by the complete income. Thus,

APC = C/Y, whereby

APC stands for mean propensity come consume,

C because that amount of consumption, and

F for the level of income.

In the Table 6.1 it will be viewed that in ~ the level of earnings Rs 1000 crores, intake expenditure is equal to Rs. 750 crores. Therefore, mean propensity to consume is right here equal to 750/1000 = 0.75. Likewise, once the income rises to Rs. 1200 crores, intake rises come Rs. 900 crores.

Therefore, the typical propensity to consume will be 900/1200 = 0.75. In this schedule of usage function, the average propensity to consume is the exact same at every levels that income. Keynesian con­sumption duty CC is presented in Fig. 6.3.


Average propensity to consume at a suggest on the consumption duty curve can be obtained by measure up the slope of the beam from the origin to that point. For example, at revenue level OY1 corresponding suggest on the consumption duty curve is A. Therefore, in ~ OY1 revenue level, aver­age propensity to consume (APC) is the slope of the beam OA.

Similarly, at earnings level OY2, average propensity come consume is the slope of the beam OB. It will be observed from Fig.6.3 the slope that OB is less than the of OA. Therefore, median propensity to consume at revenue level OY2 is less than that at income level OY1. In other words median propensity come consume has declined with the increase in disposable income.

Non-Linear intake Function: Average and also Marginal Propensity to Consume:

In the consumption role depicted in Fig. 6.3, though typical propensity come consume (C/Y) declines, marginal propensity to consume which equals ΔC/ΔY remains continuous since consumption duty curve CC’ is a directly line and also therefore its steep (ΔC/ΔY) is constant.

But that is not necessary that marginal propensity come consume need to be the exact same at every levels the income. We have constructed below an­other schedule the consumption role in i beg your pardon marginal propensity come consume de­clines through the rise in income.


It will be checked out from Table 6.2 that at the level of income of Rs. 100 crores, marginal propensity to consume is 0.9, and also when revenue rises to Rs. 1500 crores, the marginal propensity to con­sume has declined to 0.5. When with the rise in income both marginal propen­sity to consume and average propensity come consume decline, climate the curve that consumption duty is no a right line however has a form as presented in Fig. 6.4.

From any allude on the propensity to con­sume curve CC we can uncover out mean propensity come consume by joining that point with the point of origin by a straight line who slope will certainly measure the typical propensity come consume.

In Fig. 6.4, if we have actually to uncover out median propensity come consume at allude A top top the consumption function curve CC’, us connect allude A v the beginning by a straight line. Now, the steep of the heat OA i.e., AY1/OY1 will indicate the typical propensity to consume.

Similarly, at allude B of the offered consumption function CC’, the average propensity to consume will be offered by the slope of the line OB which is same to BY2/OY2. The glance in ~ the figure will present that the slope of the line OB is smaller sized than the slope of the line OA. Therefore, typical propensity to consume at suggest B or at revenue level OY2 is much less than that at point A or earnings level OY1.

Table 6.2. Non-Linear consumption Function: Average and Marginal Propensity come Consume:


Marginal Propensity to Consume:

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The ide of marginal propensity come consume is an extremely important, since from the we have the right to know how much part of the increment in earnings is consumed and also how much saved. Marginal propensity come consume is the ratio of change in usage to the adjust in income.



where, MPC represents marginal propensity to consume,

ΔC for change in consumption, and also

ΔY for adjust in income.

Marginal propensity come consume demands to be closely distinguished from mean propensity to consume. Whereas mean propensity come consume is the ratio of full consumption to complete income, i.e., C/Y, the marginal propensity come consume is the ratio of readjust in consumption to the readjust in income, i.e. ΔC/ΔY.

The ide of marginal propensity to consume deserve to be easily construed with the help of Table 6.2, in column 4 of i beg your pardon we have actually calculated the marginal propensity come consume at various levels of income. In this schedule when revenue rises indigenous Rs. 1000 main point to Rs. 1100 crores, the consumption increases indigenous Rs. 950 crores to Rs. 1040 crores. Below the increment in earnings is Rs. 100 crores and the increment in consumption is Rs. 90 crores. Therefore, marginal propensity come consume which is ΔC/ΔY is below equal come 90/100 or 0.9.

Similarly, once national earnings rises to Rs. 1200 crores and as a result consumption boosts from Rs. 1040 crores to Rs. 1120 crores, the marginal propensity come consume is now equal come 80/100 or 0.8. In Table 6.2, it will certainly be seen that marginal pro­pensity to consume decreases as the earnings rises.

It is worth noting that when with the boost in earnings average propensity come consume declines, marginal propensity come consume is less than average propensity to consume. This is- in accordance v the usual relationship between the average and marginal quantities. This is obvious from Ta­ble 6.2.


But when typical propensity come con­sume remains consistent as in Table 6.1, mar­ginal propensity to consume is same to it. In Table 6.1, median propensity to consume re­mains continuous at 0.75 and also from its 4th col­umn it will certainly be viewed that marginal propensity to consume is also 0.75.

Marginal propensity come consume can be estimated by drawing the tangent in ~ a point on the consumption function. Think about Fig. 6.5 where curve CC showing the consumption duty has to be drawn. Marginal propensity to consume at point A on this will certainly be equal to the steep of the tangent tt’ attracted at this point.

Similarly, marginal propensity come consume at allude B on it is offered by the slope of the tangent JJ’ drawn at this point. It will certainly be checked out that slope of the tangent JJ’ is much less than the steep of the tangent tt’. Therefore, marginal propensity to consume at allude B on the consumption role CC in Fig. 6.5 is smaller than the marginal propensity to consume at allude A top top this usage function.

Thus, marginal propensity to consume is declining with the increases in revenue in the non-linear consumption function curve CC in Fig. 6.5. Therefore when marginal propensity come consume decreases with the boost in income, consumption function is non-linear who slope decreases as income rises. Non-linear consumption role is displayed in Fig. 6.5 wherein the slope of the propensity to consume curve CC declines as earnings increases.

In Fig. 6.1 and Fig. 6.3 propensity to consume curve is a directly line i.e., the slope of the consumption role curve continues to be constant. Therefore, marginal propensity come consume which is provided by the steep of the propensity come consume curve remains continuous in Fig. 6.1.

It is precious noting that marginal propensity to consume is no zero nor equal to one. It has been uncovered by empirical researches that marginal propensity come consume varies in between zero and unity. If the marginal propensity to consume to be zero, then the whole of the increment in income would have been saved and also the consumption function curve would have a horizontal shape.

As we have actually seen before, this is no so realistic. ~ above the other hand, if the marginal propensity come consume was same to unity, then the whole of the increment in revenue would be consumed and in that case consumption role curve would have coincided with 45° line.

Saving Function:

As discussed above, consumption increases as revenue increases but less 보다 the increase in income. We will now explain what happens to saving when earnings increases. Saving is identified as the component of earnings which is not consumed because disposable income is one of two people consumed or saved.


Y = C + S

S = Y – C

where Y = Disposable income, C = Consumption, S = saving

Like consumption, conserving is likewise a function of income. Thus, saving function can be composed as

S= f(Y)

Saving role is a equivalent of a usage function, Therefore, provided a certain consumption, function, we have the right to derive the matching saving function. Let us take the Keynesian consumption, namely, C = a + bY. We deserve to derive saving role corresponding come it.

Since Y = C + S

S = Y – C

Now, substituting the above Keynesian duty for C in (i) we have actually

S = Y – (a + bY)

= Y – a – by

= – a + Y – by

= – a + (1 – b) Y

Note the (1 – b) in the over saving function in (ii) is the value of marginal propensity to conserve where b is the worth of marginal propensity come consume. Allow us provide a numerical example. Mean the adhering to consumption duty is given.

C = 150 + 0.80 Y

S = Y – C

Substituting the offered consumption function for C we have actually

S = Y – 150 – 0.80 Y

= – 150 + Y – 0.80 Y

= 150 + (1 – 0.80) Y

= – 150 + 0.20 Y

Note the 0.20 to represent marginal propensity come save. It also follows from over that the sum of marginal propensity to consume and also marginal propensity to save is same to one (MPC + MPS – 1). The is essential to distinguish between average propensity to save and marginal propensity to save.

Average propensity come save:

An important relationship between income and also saving is described by the ide of mean propensity come save. (APS). Mean propensity to conserve is the relationship of disposable earnings that is conserved (i.e. Not consumed). Mathematically

APS = Savings/Disposable revenue = S/Y

Like the median propensity to consume (APC) median propensity to save also generally different as revenue increases. As checked out above, typical propensity to consume (APC) falls as income increases. This indicates that mean propensity to save will rise as revenue rises.

Let united state derive critical relationship between average propensity come consume and also average propensity to save.

Restating below the relation that income is one of two people consumed or saved:

C + S = Y

Dividing both political parties by disposable income Y we have

C/Y + S/Y + Y/Y = 1

Since C/Y is median propensity to consume and S/Y is average propensity come save, we have actually

APC + APS = 1

or APS = 1 – APC

This way for example, that if a culture consumes 75 every cent the its dis­posable income, the is, APC = 0.75, then it will conserve 25 per cent the its dis­posable revenue or its average propen­sity to save (APS) will certainly be 0.25 (1 – 0.75 = 0.25).

In Fig. 6.6 we have attracted the sav­ing curve SS in the panel at the bottom. The saving curve SS shows the space be­tween intake curve CC and also the revenue curve OZ in the top panel that Fig. 6.6. It will be viewed that up to in­come level OY1 usage exceeds income, that is, there is dissaving.

Be­yond revenue level OY1, there is confident saving. The is worth discussing that as average propensity come consume (APC) falls with the increase in income in the top panel average propensity to save rises as revenue increases. Thus in Fig. 6.6 v the increase in income not only the absolute amount of saving increases, the median propensity come save additionally increases.


Marginal Propensity to conserve (MPS):

Whereas average propensity to save suggests the proportion of revenue that is saved, marginal propensity to conserve represents just how much of the additional disposable income is specialized to saving. The marginal propensity to conserve is therefore readjust in to save induced by a readjust in the disposable income.



For example, if disposable revenue increases from rupees 10,000 to 12,000 and also this causes planned savings to increase by Rs. 500 crores, marginal propensity to conserve is:

MPS = 500/2000 = 1/4 = 0.25

Since the additional income is either consumed or saved, the sum of marginal propensity come consume and also marginal propensity to save is same to one.

MPC + MPS = 1

This have the right to be mathematically verified as under

From C + S = Y, it adheres to that any readjust in revenue (AF) must induce either change in usage (AC) or adjust in saving (AS). Thus.

ΔC + ΔS = ΔY

Dividing both sides by ΔY we have

ΔC/ΔY + ΔS/ΔY = ΔY/ΔY = 1

MPC + MPS = 1

The principle of marginal propensity to save is graphically presented at the bottom that Fig. 6.6. It will be watched from this figure that once disposable earnings increases indigenous OY1 (say Rs. 10,000) come OY2 (say Rs. 12,000), the is, ∆Y = Rs. 2000, the saving increases by Y2T, (Rs. 500), the is, ΔS is Rs. 500. Hence marginal propensity to save (MPS) is

ΔS/ΔY = Y2T/Y1Y2 = 500/2000 = 1/4 = 0.25

Keynes’s theory of Consumption:

Keynes in his “General theory”, released in 1936, set the foundations of modern macroeconomics. The ide of consumption duty plays vital role in Keynes’ concept of income and employment. Keynes stated several subjective and objective components which determine consumption of a society. However, according to Keynes, of all the factors it is the present level of income that identify the intake of an individual and additionally of society.

Since Keynes laid stress on the absolute dimension of present income together a determinant that consumption, his theory of consumption is additionally known together absolute income theory that consumption. Further, Keynes placed forward a psychological regulation of consumption, according to which, as income increases consumption increases however not through as much as the rise in income. In other words, marginal propensity to consume is much less than one.

1> ΔC/ΔY>0

While Keynes recognized that numerous subjective and also objective factors including attention rate and also wealth affected the level consumption expenditure, the emphasised the it is the existing level of income on i beg your pardon the intake spending of an individual and the society depends.

To quote him:

“The amount of aggregate consumption depends mostly on the lot of aggregate income. The an essential psychological law, ~ above which we are entitled to rely with an excellent confidence both a priori from our knowledge of human being nature and from (the detailed facts of experience is that males (and women, too) are disposed, together a rule and on an mean to rise their consumption as their revenue increases, but not by as lot as the boost in their income.”

In the over statement around consumption behaviour, Keynes makes three points. First, he suggests that intake expenditure depends greatly on absolute income of the current period, that is, intake is a positive role of the pure level of existing income. The an ext income in a period one has, the more is most likely to be his consumption expenditure in the period. In various other words, in any period the rich human being tend to consume much more than the bad people do. Secondly, Keynes points out that intake expenditure does not have actually a proportional connection with income.

According to him, as the revenue increases, a smaller sized proportion of revenue is consumed. The ratio of consumption to earnings is dubbed average propensity to consume (APC). Thus, Keynes suggests that typical propensity to consume (APC) drops as revenue increases.

The Keynes’ consumption function can be expressed in the following kind

C = a + bYd

where C is intake expenditure and also Yd is the actual disposable earnings which equals gross national income minus taxes, a and b space constants, where a is the intercept term, that is, the quantity of usage expenditure in ~ zero level the income. Thus, a is autonomous consumption. The parameter b is the marginal propensity come consume (MPC) which measures the increase in intake spending in solution to per unit boost in disposable income. Hence


Since the mean propensity to consume falls as revenue increases, the marginal propensity to consume (MPC) is less than the median propensity come consume (APC). The Keynesian con­sumption function is portrayed in Figs. 6.3.

In Fig. 6.3 we have shown a direct consumption role with one intercept term. In this type of linear intake function, despite marginal propensity to consume (ΔC/ΔY) is constant, typical propensity to consume is decreasing with the rise in earnings as indicated by the slopes that the currently OA and also OB at levels of income Y1 and also Y2 respectively. The directly line OB drawn from the origin indicating typical propensity come consume at greater income level Y2 has a relatively less slope than the directly line OA attracted from the beginning to point A in ~ lower earnings level Y1.

The decrease in typical propensity come consume as the earnings increases implies that the ratio of income that is saved rises with the increase in national revenue of the country. This result also adheres to from the researches of household budgets the various households at different income levels. The portion of income spent on intake by the rich family members is reduced than that of the negative families. In various other words, the rich households save a higher proportion the their income as compared to the bad families.

The presumption of diminishing median propensity come consume is a significant part that Keynesian concept of income and employment. This means that as revenue increases, a progres­sively larger proportion that national revenue would it is in saved. Therefore, to attain and keep equilibrium at full-employment level of income, boosting proportion that national earnings is required to be invested.

If sufficient investment avenues are not available, the economic climate would climate run right into trouble and in that case it would certainly not be feasible to maintain full-employment because aggregate demand will fall brief of full-employment output. ~ above the basis of this in­creasing ratio of saving with the boost in income and also consequently, the development of the trouble of need deficiency, part Keynesian economists based the theory of secular stagnation on the declining propensity come consume.

Determinants of Propensity come Consume:

The essential question is on what components the propensity to consume the a neighborhood depends. In other words, what room the determinants that recognize the level and position of the pro­pensity to consume or the consumption function? Keynes split the factors determining the propensity to consume into two groups: the very first group of components was dubbed by him as subjective factors and also the 2nd group was called by him as objective factors. Us shall explain listed below in detail these subjective and objective determinants which influence the consumption function of a com­munity.

Subjective Factors:

Among the subjective factors are contained those components which induce and prompt world to save some part of your income. First, people save due to the fact that they desire to administer for unexpected contingencies, such together illness, unemployment, accidents, etc. Secondly, civilization are induced come save since they desire to provide for the meant future needs such as education and learning of the children, marriages of your children, etc.

Thirdly, several civilization wish to save from their present incomes so the they may be able to use collected savings for invest which will increase their future income. Invest will lug them more income in the kind of an ext profits and interest. Fourthly, people are motivated to save so the they deserve to accumulate large wealth i m sorry will boost their social status.

With raised wealth they would certainly think us to be economically more independent and also they could buy plenty of things with an ext wealth. Further, plenty of individuals additionally save so the they have the right to use them for speculative pur­poses and also other company projects.

Besides, several civilization are prompted to conserve for the services of leaving a good fortune for your heirs and also children. Lastly, many human being save since of your miserly instinct and habits. The buildup of more wealth provides them a great psychic satisfaction.

The over subjective components increase the propensity to save and therefore minimize the pro­pensity come consume. This subjective components play a crucial rule in determining the level and shape the the consumption function. However, Keynes sharp out and also rightly therefore that part subjective determinants raise the propensity come consume.

The desire because that ostentation generally leads to greater intake expenditure. World have a herbal in insignificant to imitate others’ intake habits. As stated by Duesenberry, people in lower and also middle income ranges imitate the usage standards that the greater income groups and this increases their propensity to con­sume. This has actually been referred to as demonstration impact which is a an excellent subjective or psychological pressure that works in elevating the propensity come consume.

Subjective factors also lead the company firms come save much or tiny from their incomes.

Many that the subjective determinants which affect the save of the firms room the following:

(1) Enterprise:

Many business industrial this firm desire to conserve a part of their present income so the they deserve to make invest in new enterprises and also carry out development in the future. Busi­ness firms normally save a an excellent part the their earnings for their additional expansion.

(2) Liquid­ity:

Business firms likewise are induced to save so that they can challenge contingencies in the future. If lock have an excellent amount of liquid wide range in their hands, they would be able to meet the emergent situations much more successfully. More cautious and farsighted firms will save an ext than others on this count.

(3) successful Management:

Many supervisors of the business firms are encouraged to save much more because they want prove themselves successful managers. Through the investment of the conserved money, the revenue of a firm increases and their managers are pertained to as successful.

(4) gaue won Prudence:

Business this firm desire to save for consisting of the depreciation in plant and machinery. Due to the fact that after some years service firms have to replace their plant and machinery, if a great part of their existing income is not saved, it would certainly not be feasible for them to change plant and machinery.

If the firms placed aside a greater component of their revenue for depreciation or replacement purposes, they would certainly pay reduced dividends come the shareholders and also this will typically lower the propensity to consume that a community.

On the other hand, if the firms store a fairly small amount because that depreciation, they will certainly pay larger quantities as dividends to the shareholders and also this will normally increase the propensity to consume that the community. Lastly, firms likewise want come save due to the fact that they need to repay your debts.

Objective Factors:

Keynes mentioned the following six varieties of objective determinants which influence the con­sumption function:

(1) alters in the general Price Level: real Balance Effect:

The basic price level is an important factor which impacts the intake of a community. When the basic price level rises or, in various other words, when inflation occurs, the consumption role shifts downward. This is due to the fact that the climb in the basic price level, real value (that is, purchase power) that people’s money balances and also financial assets v fixed monetary values declines.

This reasons a downward change in the usage function. This is dubbed real balance effect. Similarly, as soon as the general price level falls, actual value of money balances and financial legacy increases. This will induce human being to consume relatively an ext out of their present income. This will cause an upward change in the intake function.

(2) fiscal Policy:

Fiscal policy of the Government, specifically taxation plan affects the propensity to consume the the country. By levy excise duties, sales tax, the government can reduced down the consumption and thereby increase savings the the community.

Likewise, once the government reduces taxes, usage of the world increases and also this raises the propensity come consume. Rationing and price control by the Government additionally affects the propensity to con­sume, together was witnessed throughout the 2nd World War.

In the contemporary times, pursuing of the welfare state policy by the federal government under which steady taxes have been levied on the well-off people and also the revenue acquired from them have been spent to administer many social security benefits and amenities come the poor people, has actually tended to raise the usage function.

(3) price of Interest:

Rate the interest additionally affects the propensity to consume and save. It is generally thought that greater rate of attention induces the civilization to save more and this outcomes in reducing their propensity to consume. Yet this is no true in the case of all the people. Some individuals are of such a type who desires a specific fixed income in the future.

And when the price of attention rises these people consume an ext and conserve less because with greater rate of attention they can obtain the given fixed income with lesser savings. Therefore, when the price of interest rises such individuals save less than before. Thus, it can not be said with certainty whether with the alters in the price of interest the propensity to consume of the entirety com­munity will adjust or not.

(4) share of Wealth:

The stock of riches owned by the family members in the economic climate is also critical factor the determines propensity come consume. In wide range we include not only real legacy such together land, houses, automobiles but also financial heritage such together cash balances, saving and fixed deposits with banks, stocks and also bonds own by households. The higher the quantity of wealth accumulated by households in the economy, the higher is typically the propensity to consume (i.e. The higher the quantity of intake out of any type of level of existing income).

The important motive that the civilization to save is come accumulate wealth. Normally speaking, the greater the wide range which civilization have accumulated, the weaker is the catalyst to save further. In other words, the various other things staying the same the increase in riches generally reasons an upward transition in the consumption function and diminish is wealth reasons a downward shift in the usage function.

An essential example i beg your pardon is often cited to emphasize the importance of riches as a determinant of consumption is the stock industry crash the 1929 in England (i.e. Drastic autumn in re-superstructure prices) which substantially reduced the financial riches of the families overnight re­sulting in moving the consumption duty downward.

(5) credit Conditions and Consumer Indebtedness:

The ease of access of easy credit causes rise in consumption and also shifts the consumption function upward. That is currently a common experience in India the in recent years lowering of loan interest rates by Indian financial institutions on loans because that houses, cars, computers and also other durable consumer goods has considerably increased the consumption of the people and also shifted consumption function upward.

On the other hand, tight­ening of credit produces an the contrary effect, that is, causes a downward shift in the consumption function, Furthermore, the recent boost in infrastructure of credit Cards through banks and their ac­ceptance buy sellers of customer goods have likewise worked to transition the consumption role upward in India.

Similarly, the level of consumer indebtedness likewise greatly affects the propensity to consume of the people. If the family members are heavily indebted, say 25 come 30 every cent of your current, they are committed to conserve (i.e. Consume less) come that level so that they are able to pay their installments of previous credit transaction taken. Thus, the greater the level of indebtedness of households in the economy, the greater will be the consumption duty curve and vice versa.

(6) earnings Distribution:

Lastly, distribution of revenue in a society also determines the level of usage function. If national revenue is an ext unequally distributed, the reduced will be the propensity to consume. This is because propensity to consume that the well-off is fairly less as compared to that of the poor. Therefore, if inequalities in income circulation increase, this reduce the intake out of any given level of nationwide income and thus causes a downward shift in the usage function.

(7) Windfall Gains and Losses:

Windfall gains and losses also impact the propensity to consume. Once the price of the shares go up, the shareholders begin to think themselves far better off and also this raises their consumption. Top top the other hand, as soon as the prices of the shares go down, the shareholders have to suffer suddenly losses and they begin to think themselves fairly poorer 보다 before. This induces castle to reduce their consumption. We for this reason see the the windfall gains and also losses affect the propensity come consume.

(8) change in Expectations:

Changes in the expectation of the people likewise influence the propensity come consume. When civilization expect that war will an episode in the near future and also they suppose prices to go up, climate they will shot to spend an ext on products so regarding meet the requirements of the prompt future.

This raises the consumption function in the existing period. On the other hand, when civilization expect the prices to autumn they alleviate their current usage so that they should spend an ext when the prices in reality fall.

We have actually explained over various subjective and objective factors which bring away together identify the consumption role of a community. It is worth noting the propensity come consume does not generally adjust in the brief run, because it depends more on psycho­logical and institutional factors which change only in the long run.

The institutional components which identify the circulation of earnings in the culture are essential forces identify the usage function. And also these institutional components do not change in the quick run. Therefore, Keynes was of the view that consumption function remains secure in the short run.

Important features of Keynes’ intake Function:

In macroeconomics, Keynes’s consumption duty plays a highly essential role. There­fore, the is necessary to state its necessary features.

The following are the essential features of Keynes’s intake function:

1. First, pure level of present income is the necessary factor that determines con­sumption that the community. Rise in national revenue causes boost in con­sumption. Top top the various other hand, timeless economists assumed that the was price of interest that primarily identified saving and also consumption that the community. A climb in rate of attention induces the people to save more and thus to reduce their level that con­sumption.

According come Keynes, though rate of interest is among the determinants that determine consumption of the community, the did not take into consideration it a really important determinant that it. By considering level of existing income together the most necessary factor identify consumption and saving, Keynes do a far-ranging contribution come the macroeconomic theory.

2. The second important attribute of Keynes’ consumption duty is that marginal pro­pensity to consume is less than one but greater 보다 zero (0


We chandelier critically study Keynes’s consumption duty and compare it with various other theories of usage function.

Consumption duty Puzzle: Keynes’ Consumption role and Kuznets Findings:

Empirical research studies of irreversible times collection data the the US economic climate for the period 1869- 1938 make by the listed American economist Kuznets estimated a consumption duty which contradicts Keynes’ consumption duty which was uncovered to be exactly on the communication of cross- section studies the household budget plan data and short-term time collection data.

This contradiction in between Kuznets empirical findings and also Keynes’ consumption role has been called con­sumption duty puzzle. Initiatives have to be made through several economists to solve this puzzle and brand-new theories that consumption duty have been put forward to resolve the conflict between Keynes’s consumption function and Kuznets’s findings.

To to compare the Keynes’ and Kuznets’s intake functions, it will certainly be useful to create them in algebraic type and graphically stand for them.

Keynes’s consumption function can be algebraically written as below:

C = a + by

where a is a positive intercept term which is also called autonomous intake as the does no vary through income. The consistent a shows that also when income is zero, a details con­sumption is present. This is possible when in any year a ar can live one of two people on its past savings or borrow from other communities. Keynes’ consumption function is shown in Fig. 6.7.

Secondly, b in the consumption function represents marginal propensity to consume (ΔC/ΔY). The over mentioned Keynes’s consumption function (C = a + bY) reflects that mean propensity to consume (C/Y) drops as earnings increases. This can be well-known by comparing slopes that the beam OA one OB at earnings levels Y1 and also Y2 dong in Fig. 6.7.

Kuznets’s intake Function:

On the other hand, Kuznets found that consumption role is of the adhering to form:

C = bY

In Kuznets’ consumption function there is no intercept term (that is, autonomous con­sumption). This is displayed in Fig. 6.8 where it will be viewed that Kuznets consumption function curve starts from the origin and is very near to 45° line depicting that the propensity come consume (b) is really high. Indigenous his empirical research Kuznets approximated that typical propen­sity come consume was practically 0.9.

Besides, by dividing the entire period (1869-1933) right into three end lapping 30 years sub-periods Kuznets found that the proportion of usage to revenue (that is, mean propensity to consume) was practically the same and equal to around 0.87 in all the three sub-periods.

Thus Kuznets concluded that there to be no propensity for the mean propensity come consume to decline as disposable earnings rises. Thus, round off off Kuznets estimated propensity to consume is equal to 0.9. His consumption function presented in equation (2) deserve to be rewritten together

C = 0.9 Y

From the over discussion it follows that implicitly of Keynes’s consumption function (C = a + bY) and Kuznets consumption role (C = bY) room different. Whereas in Keynes’ consumption function APC falls as earnings rises, in Kuznets’s function it remains consistent over a long period. Further, the worth of marginal propensity come consume i m sorry is much less than one is much greater in Kuznets’s role as compared to that of Keynes.

The reconciliation between two types of intake functions has actually been made by some economic experts by mentioning that conversely, Keynes’s duty is short-run consumption duty Keznets’s role is came to with lengthy run and also is referred to as long-run intake function. In the long run, short run consumption function curve shifts over and thus in the lengthy run intake function, propensity to consume is higher as contrasted to the in the short run.

Further, Friedman’s permanent income Hypothesis and Modigliani’s Life Cycle hypothesis have likewise tried come reconcile the two attributes by referring to the short-run and long-run usage behaviour of the people. Us will discuss these usage hypotheses in the appendix.

Importance of intake Function:

The principle of consumption function is greatly necessary both in theory and also actual practice. To remove unemployment and also to control economic fluctuations in the economy, that is very es­sential to embrace a ideal macroeconomic policy. In the development of such a policy, understanding of the ide of propensity the consume is an extremely essential. Therefore, Prof. A.H. Hansen has remarked that “consumption duty is epoch-making contribution of Keynes to economic the­ory”.

We chandelier explain listed below some the the theoretical and also practical importance of this consump­tion function:

(1) The principle of consumption role helps united state to invalid Say’s legislation of classical economics. In fact, Keynes relied ~ above his consumption duty for proving the invalidity that Say’s law. According to Say’s law, every supply creates its very own demand and also therefore there is no problem of deficiency of accumulation demand. Therefore, basic overproduction and also unem­ployment in the economy is not possible because sufficient amount of aggregate demand is ever before present. Now, follow to the Keynesian consumption function, when earnings increases con­sumption boosts less 보다 the increase in income and therefore saving gap emerges between income and consumption.

This saving space implies that all output produced may not be sold and also the trouble of deficiency of need will arise uneven this saving space is matched by an same amount of invest demand. There is no guarantee the the saving done will be immediately invested or, in other words, the is not crucial that investment demand will be same to the saving gap. Thus, the contention the the Say’s regulation that every supply creates that equal demand is no valid. No doubt, every it is provided or production creates income equal to the calculation produced.

But due to the fact that all revenue is not consumed and also there is no guarantee that investment will be equal to the conserving so emerged, Say’s legislation is confirmed invalid. Once investment is much less than the conserving gap corresponding to full-employment level the income, the accumulation demand is not enough to provide full-employment to the people and also other resources. Thus, the difficulty of deficiency of effective demand and hence general unem­ployment and also overproduction occurs in a free enterprise capitalist economy.

(2) The ide of propensity to consume is also important due to the fact that it bring out critical significance of investment demand for determination of the level that income and also employment in a capitalist economy. From the concept of propensity come consume we understand that consumption increases much less than the rise in income and as a result gap emerges in between income and consumption.

To preserve a details given level the income and also employment, gap between income and consumption at the level have to be bridged by invest expenditure otherwise it will certainly not be feasible to maintain that level of income and employment because aggregate demand would certainly not be huge enough.

This indicates the critical importance the the investment need in the determination of income and employment. To stop the establishment of underemployment equilibrium in the economy or, in various other words, because that achieving full-employment equilibrium, in­vestment demand must be same to the saving void at the level of full-employment. Keynes also showed that consumption function remains steady in the brief run and therefore economic fluc­tuations in a capitalist economic climate are largely because of the fluctuations in investment demand.

Thus indigenous the ide of propensity to consume it follows that investment demand is vitally vital in identify the level that income and employment. If it were possible to advanced the propensity come consume in the brief run, climate without increasing investment, we can have raised the level the income and also employment. Due to the fact that propensity to consume at a given level the income normally remains stable, we have to increase investment for achieving complete employment in the economy.

(3) Another critical importance of the principle of propensity to consume is that we derive the theory of multiplier from that which has great practical importance in the formulation that macro-economic policy, particularly of public works in time of depression.The magnitude of multiplier is same to the mutual of one minus marginal propensity to consume (K = 1/1-MPC) wherein K means multiplier and MPC because that marginal propensity come consume. Follow to this principle of multiplier, as soon as investment increases, in­come, output and employment boost by a multiple amount, depending upon the size of the multiplier.

Income increases manifold than the original investment due to the fact that of the nature of usage function. Once some invest in some tasks is undertaken, it leader to the increase in earnings of those employed in the projects but the process does not prevent here.

The increases in earnings are further spent ~ above consumption and this leader to further increase in income and so the chain of increases in income and also consumption continues and the ultimate boost in income and employment is multiple of the original increment in investment.

If the marginal propensity come consume were equal to zero, then every increments in earnings brought around by extr investment would have been saved and also therefore multiplier procedure would not have worked. Since the marginal propensity to consume is better than zero, the boost in net investment has actually a multiplier effect on income, output and employment. Thus, the impact of invest on earnings depends top top the dimension of the multiplier which relies on the value of the marginal propensity to consume. The better the marginal propensity to consume, the better the size of the multiplier.

(4) from the ide of consumption function, us can also explain why there is a tendency for the marginal efficiency of funding to decline. The declining propensity of the marginal effi­ciency of funding is due to the nature of the usage function. Two attributes of consumption role are important. First, the marginal propensity come consume is much less than one which suggests that as income increases, consumption increases much less than this. Secondly, consumption role is steady in the brief run i.e., it does not transition much in the brief run.

As we understand that the level of invest is a vital factor in the determination of income and also employment, fluctuations in the level of income and employment depend generally on the fluctuations in investment. The investment need in the short run is established by the price of attention on the one hand and marginal efficiency of resources on the other. Because the rate of attention is reasonably sticky, it is the marginal efficiency of capital which greatly affects the level of invest in the brief run.

Marginal performance of funding is nothing however the expected price of benefit on invest in the future. Thus, the marginal efficiency of capital is figured out by the expectation of the entrepreneurs concerning the earning of profits from resources assets in the future.

Now, the most, essential fact the affects the entrepreneurs expectations concerning profit prospects and also thereby the marginal performance of capital is the level the future consumption demand for goods and also services. Their calculation of future usage demand relies on, amongst others, on the population growth. If population growth that a country is meant to loss as was estimated in the early thirties once Keynes created his book (General concept of Employment, Interest and also Money), this would adversely impact future usage demand which subsequently would adversely impact investment in the lengthy run, Besides, follow to Keynes, typical propensity come consume (APC) falls as earnings of a ar increases overtime.

This additionally adversely affects inducement to invest. If over there does not occur capital-using technological change, this will result in decline in investment opportunities in the long run, resulting in secular stagnation. For this reason we watch that in the Keynesian plan of points level that investment relies upon the level of consumption demand in the lengthy run.

Since marginal propensity come consume is less than one and likewise the consumption duty is secure when earnings increases, usage does not increase proportionately. As a result, the accumulation demand becomes deficient and the marginal efficiency of capital declines. The decline in the marginal effectiveness of funding adversely affects investment which stops rising. Together a result, the growth process stops and also economic recession occurs.

In this way, Keynes himself and later necessary Keynesian economist, Prof. A.H. Hansen emerged the concept of secular stagnation for the tires capitalist economies. This secular stagnation theory is based upon the assertion the investment opportunities in a capitalist economic climate will be worn down soon because of the lack of the possibilities the increasing consumption demand. The meagre possibilities of boosting investment in the maturation capitalist economies, according to them, were partly as result of the constancy of consumption function and decreasing average propensity to consume which led to the marginal performance of capital to decline.

Theory that secular stagnation has not been found true through empirical proof in the last end seventy year of development in the capitalist emerged countries. However, the fact that current consumption is influenced by changes in rate of interest, share of wealth and also price level and also further that it is the changes current intake level that recognize short-run organization expectations about future returns from investment which cause fluctuations in investment.

Together v the working of multiplier fluctuations in investment cause company cycles in a complimentary market economy. This shows the an excellent importance the Keynes’s consumption function and the components that determine it.

(5) As has been described above, Keynesian concept of propensity to consume likewise helps united state in explaining the transforming points of a business cycle. The economy swings down from the height it reaches because with marginal propensity come consume being much less than one and also average propensity come consume falling intake demand walk not boost as lot as the increase in income and also output. In time this causes deficiency in accumulation demand which adversely influence investment demand by private business men.

Likewise, economy’s downward activity stops and it start recovery since marginal propensity come consume being much less than one, human being do not mitigate their intake as much as the reduction in their income. Even throughout depression people shot to preserve their ahead level the consumption. This eventually induces investment for replacement of funding goods which wear the end over a duration of service cycle. With the working of Keynesian investment multiplier recovery from recession gathers momentum.