HC Deb 31 July 1958 vol 592 c165W
65. Mr. Leather

asked the Chancellor of the Exchequer the formula relating the output of various major industries which is used in compiling the overall Index of National Production.

Mr. Maudling

The formula is by percentage increases or decreases since 1948 in volume of output of each industry in proportion to its contribution to total production in that year.