What is the tax index number for capital gains in India?

Tax index number is the technique used to find out the current moneytary value of a capital asset so as to find out the difference between the sale proceeds and the value thus found out by applying the index for the purpose of charging tax on the difference. For this purpose 1981 is taken as the base year and it has been assigned an index no of 100, which is calculated on the basis of wholesale price index and the level of inflation in the economy.