Washington: Metro - nonmetro Source: 2018: U.S. Bureau of the Census, Metropolitan and micropolitan statistical area definitions (from OMB), (https://www.census.gov/programs-surveys/metro-micro.html); (https://www.census.gov/geographies/reference-files/time-series/demo/metro-micro/delineation-files.html); US Department of Agriculture, Economic Research Service, Rural-Urban Continuum Codes, (http://www.ers.usda.gov/data-products/rural-urban-continuum-codes.aspx); Urban Influence Codes, (http://www.ers.usda.gov/data-products/urban-influence-codes.aspx); DATE LAST UPDATED: July 26, 2018. 2017: (https://www.whitehouse.gov/sites/whitehouse.gov/files/omb/bulletins/2017/b-17-01.pdf);