The Louisville-Jefferson County, KY-IN Metropolitan Statistical Area (MSA), the 43rd-largest in the United States,[REF] includes the Kentucky counties of Jefferson (coterminous with Louisville Metro), Bullitt, Henry, Meade, Nelson, Oldham, Shelby, Spencer and Trimble.
Louisville's Metro Area was expanded more than any other in the country during a March 2003 overhaul of U.S. Metropolitan Area statistics by the federal government.