Value Index Numbers
The value index number as described earlier is a combination index which combines price and quantity changes. Because of the difficulties experienced in price and quantity indices, the usage of the value index has been suggested. The value index number can be calculated by the following formula,
where, P1, Q1, P0 and Q0 follow the usual notations.
Interestingly, in value indices, weights need not be used as they are inherent in these indices. The value index, an aggregate of all values, measures the changes in values in the base year and the values in the given year. The value index can also be obtained by the product of price and quantity indices. Let us calculate the value of some equity shares owned by an investor on July 27, 20x1 relative to the value of the shares owned by him on Jan 8, 20x0 as measured by the value index.