Year	constant 2011 international $
1990	19556.6658397948
1991	20192.8495123606
1992	19045.8427147924
1993	19274.5961944987
1994	19470.689011716
1995	19917.4649358817
1996	20120.0626347179
1997	20745.5645043115
1998	20940.0810229207
1999	18608.5131021788
2000	17822.4922378501
2001	17774.11595021
2002	17312.6973156444
2003	17277.4763907321
2004	16961.7336736011
2005	16955.3457342617
2006	16023.1397552377
2007	16496.4873678855
2008	15467.8971214347
2009	14990.6391350679
2010	15507.7275528356
2011	16011.1245045144
2012	16225.3875240525
2013	16504.613134815
2014	16606.9190226429
2015	16685.2323042237
2016	16523.5857795859
2017	16144.9352967905
2018	15922.1932591456