On This PageAugust 1989, No. 24

July of 1989's Chicago Fed Letter carried a revised version of the Midwest Manufacturing Index (MMI). This month, in our second anniversary issue, we take a look at the changes in the MMI and the underlying reasons for them.

New! Improved! The MMI Gets a Different Look
Last Updated: 08/29/89
Three distinct changes were made to the Midwest Manufacturing Index (MMI) index last month: 1) the base year was moved from 1973 to 1983; 2) the methodology was improved; and 3) a U.S. version of the MMI replaced the Federal Reserve Board's Index of Industrial Production as the national comparative index.