Census of Large-Scale Manufacturing Industries (CMI) is conducted under sections 9 & 10 of General Statistics Act 1975 and section 5 & 6 of Industrial Statistics Act 1942. The first CMI was conducted in 1954 and the last one was completed for the year 2000-01.
 

CMI covers manufacturing establishments which are registered or which qualify for registration under Factories Act, 1934. If an establishment is engaged in more than one activity and separate accounts are maintained by the establishment for each activity, then separate returns are collected for each such activity. The defence and government workshops engaged in manufacturing activities registered under Factories Act are, however excluded. The report covers the period from July 2005 to June 2006.

Production pattern and industrial structure changes over time. The CMI measures production and structural changes of large-scale manufacturing industries (LSMI). Census of Manufacturing Industries provides data on quantities and values of inputs and outputs, census value added, contribution to GDP, fixed assets, stocks, employment & employment cost and industrial taxes. It takes into account the new developments in the industrial field, capture new industrial products and establishments and develop new weights for Production Index of Manufacturing.