Year	constant 2015 US$
1991	15281.81047041348
1992	15439.254096757204
1993	15372.328886302666
1994	15074.199780556812
1995	17146.675180537557
1996	17315.45408510557
1997	17235.264355540345
1998	17430.183040903416
1999	16738.81102364334
2000	15904.045481064202
2001	17916.84883376265
2002	18277.32780601348
2003	18125.907472661114
2004	19241.323191564905
2005	19650.75380250806
2006	20118.04569136693
2007	20904.79903990363
2008	21301.688479247707
2009	21038.965470087038
2010	21973.794029470733
2011	23078.182130421057
2012	23558.99871274586
2013	23946.33203301634
2014	24459.801182199542
2015	24438.86164717144
2016	24482.79830499134
2017	25085.907586920704
2018	24681.060161206824
2019	25298.17031470737
2020	24981.600743709063
2021	25406.108458416078
2022	23696.072324240045