Year constant 2011 international $ 1990 11445.6660152543 1991 10054.0514266013 1992 9255.83620154824 1993 9410.14196934604 1994 9794.37198350147 1995 10425.9776745031 1996 10864.6530355653 1997 10367.6244470707 1998 10178.2261980941 1999 10155.8187766397 2000 10419.2582003116 2001 11117.0019204435 2002 11968.1050724769 2003 12336.9577435217 2004 13701.3158678119 2005 14429.7471633812 2006 15680.9037663144 2007 17065.4724093 2008 18967.2843046198 2009 18070.7040756282 2010 17469.1754478485 2011 17907.6746269812 2012 18361.2049364098 2013 19077.2257782884 2014 19801.9480324916 2015 20665.6363403955 2016 21782.1310204802 2017 23441.6422226294 2018 24544.0250806323