Year	constant 2010 US$
1991	7123.77683783286
1992	7355.97335316041
1993	7356.7806253037
1994	8410.54175943133
1995	8813.12251808819
1996	9408.60236901536
1997	9511.89241062271
1998	9629.34348811307
1999	9636.99118146143
2000	10331.7227901614
2001	11235.7739461042
2002	12102.2784541009
2003	13396.2255677065
2004	14308.9110710001
2005	15308.6531292684
2006	16493.1326574454
2007	18299.9284419721
2008	18205.1449434422
2009	17043.2199264319
2010	17571.4378815992
2011	18340.0832555373
2012	19851.0283252011
2013	20667.6700276062
2014	20809.6598229153
2015	20140.4557619959
2016	19756.0003664297
2017	19867.0330741725
2018	20559.9285282952