Alphabetical Index of Occupations, 1930
Classified Index of Occupations

These books were used by the Census Bureau to classify occupations reported on the population schedule. The Index standardized the classification of work and assigned each job a code, which was entered onto the punch cards used to tabulate the census.

Today the Federal Government uses the Standard Occupation Classification to classify all workers into one of 820 standardized categories of work.

Alphabetical Index of occupations, 1930 book cover
US Department of Commerce, Bureau of the Census
Washington, D.C. United States Government Printing Office, 1930
Gould Library Government Documents