Occupation and Industry Variables

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Since the early census years provide few alternative indicators of socioeconomic status, occupation and industry are among the most important variables for analyses of long-term social change. The Census Bureau has modified its classification systems every decade, so long-term studies of occupations and industries typically require extensive reconciliation of codes.

The IPUMS retains all original occupation and industry information in the OCC and IND variables. Links to each year's classification systems can be found on the OCC codes page. and the IND codes page. Census respondents described their occupations and industries in plain English. Coding rules followed by the Census Bureau and the IPUMS staff are presented for each year on the occupational coding guidelines page.

Although a complete reconciliation of these coding schemes is impossible, we provide variables that maximize the potential for consistent comparisons of occupational status and industry.

OCC1950 codes occupations from all years into the 1950 occupational scheme. OCC1990 codes occupations from 1950 onward into a modified version of the 1990 occupational scheme. IND1950 and IND1990 accomplish the same for industrial classifications.

Our essay on "Integrated Occupation and Industry Codes" describes how we construct these harmonized occupational and industry variables, as well as occupational standing variables (SEI, HWSEI, NPBOSS50, NPBOSS90, PRESGL, PRENT, EDSCOR50, EDSCOR90, ERSCOR50, ERSCOR90, and OCCSCORE). The IPUMS variables page contains a complete list of work-related variables and occupational standing variables in IPUMS-USA.

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