In 2009 the American Community Survey (ACS) added a new education data item: field of study for those who have at least a bachelor’s degree. Respondents with a degree are asked to list their specific field(s) of study. The Census Bureau codes the responses and accumulates them into 5 general fields and 15 more detailed categories. Field of study can be compared to other characteristics such as gender, age, occupation, industry of employment and income to enable those who are concerned with the relationship between higher education and our economy to better understand the educational preparation and attainment of the labor force according to occupation and industry. Read more here.