Industry based on 2002 North American Industry Classification System (NAICS). Please consult the U.S. Census Bureau (http://www.census.gov/epcd/naics02/naicod02.htm) for additional information about NAICS.
Source: US. Bureau of Labor Statistics
US. Bureau of Labor Statistics, All Employees: Mining and Logging in Illinois [ILNRMNN], retrieved from FRED, Federal Reserve Bank of St. Louis https://research.stlouisfed.org/fred2/series/ILNRMNN/, June 3, 2015.