The U.S. Census Bureau has collected and pub­lished data on industry and occupation for well over a century. The industry and occupation clas­sification system categorizes written responses into discrete numeric code lists of industries and occupations. All household Census Bureau surveys that include questions on industry and occupation use a similar methodology to assign a code. The code lists are comprised of both a numeric code and a title or description.

The two most current classifications are the 2018 Census Occupation Code List, which includes 570 detailed occupation codes and titles, and the 2017 Census Industry Code List, which includes 271 detailed industry codes and descriptions. The Census Bureau began implementing the new lists in 2018.

This report has two main objectives. First, this report describes the differences between the cur­rent and previous classification systems, specifi­cally, the 2012 Census Industry Code List and the 2010 Census Occupation Code List. Second, the report provides a methodology for comparing industries and occupations between the current and previous classifications, including detailed crosswalks with conversion rates needed to transform the data.