README for crosswalk file cw_n97_s87.dta
David Dorn

Notes: 
The crosswalk indicates the fraction of employment of a 6-digit NAICS industry that maps to a given 4-digit SIC industry, based on employment counts of the year 1997.
The crosswalk excludes industries for agricultural crop and livestock production (SIC codes 01xx and 02xx) and government (SIC codes 9xxx). The 4-digit SIC codes for agricultural services, forestry, and fishing-hunting-trapping (codes 07xx, 08xx, 09xx) are written without the leading zero, i.e., industry "711" is equivalent to industry "0711" (soil preparation services). The SIC classification includes "auxiliary industries" which support businesses in other industries. Auxiliary industries do not have a regular 4-digit SIC code but instead are only identified by the 1-digit sector they belong to. In this crosswalk, the SIC codes 20001, 30001, ..., 90001 refer to the auxiliary industries associated with the SIC one-digit sectors 2, 3, ..., 9. 


Please cite as source for this file:
David Autor, David Dorn and Gordon Hanson. "The China Syndrome: Local Labor Market Effects of Import Competition in the United States." American Economic Review, 103(6), 2121-2168, 2013.