1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, and 2009. National Energy Information Center (U.S.). This point shapefile represents natural gas market hubs in the United States for 1996-2009. A hub is a physical transfer point for natural gas wher... National Energy Information Center (U.S.).