Monday, February 2, 2015

ISM Mfg Index

The ISM manufacturing composite index is a diffusion index calculated from five of the eleven sub-components of a monthly survey of purchasing managers at roughly 300 manufacturing firms nationwide. The survey queries purchasing managers about the general direction of production, new orders, order backlogs, their own inventories, customer inventories, employment, supplier deliveries, exports, imports, and prices. The five components of the composite index are new orders, production, employment, supplier deliveries, and inventories (their own, not customer inventories). The five components are equally weighted. The questions are qualitative rather than quantitative; that is, they ask about the general direction rather than the specific level of activity. Each question is transformed into a diffusion index which is calculated by adding the percentage of positive responses to one-half of the unchanged responses