The Market Demand Curve
Quantity of a commodity that an individual is willing to buy at a particular price of the commodity during a specific time period, given his money income, his taste as well as prices of substitutes and complements, is called individual demand for a commodity. Total quantity that all the consumers of a commodity are willing to buy at a given price per time unit, other things remaining the same, is called market demand for commodity. Or we can say that market demand for a commodity is the sum of individual demands by all consumers (or buyers) of commodity, per time unit and at a given price, other factors remaining the same. For example suppose there are three consumers (A, B, C) of a commodity X and their individual demand at different prices is of X as given in Table below.
The last column presents market demand which is the aggregate of individual demand by three consumers at different prices.
|
Price of
Commodity X
(Price per unit)
|
Quantity of X demanded by M
|
Market Demand
|
|
A
|
B
|
C
|
|
10
|
4
|
2
|
0
|
6
|
|
8
|
8
|
4
|
0
|
12
|
|
6
|
12
|
6
|
2
|
20
|
|
4
|
16
|
8
|
4
|
28
|
|
2
|
20
|
10
|
6
|
36
|
|
0
|
24
|
12
|
8
|
44
|