Year	constant 2015 US$
1991	20398.3443113933
1992	19654.414197974686
1993	19764.34629222713
1994	19873.019623242515
1995	19042.736581818463
1996	18562.951568171906
1997	19236.40752861283
1998	20194.380988495068
1999	19647.879039309064
2000	19728.137325870877
2001	18984.264001077325
2002	19074.700607046914
2003	19297.155006692956
2004	18710.2352268144
2005	17033.22327792555
2006	33930.19061323301
2007	34222.22493423124
2008	34611.464515990716
2009	33700.9906020444
2010	33883.40489444745
2011	33427.79856952929
2012	34023.93554945619
2013	32995.287810967544
2014	34234.582102975335
2015	34347.31692053809
2016	33834.17655910053
2017	34627.105049777325
2018	34061.93600309708
2019	34043.33913828874
2020	29866.265699969714
2021	29612.62527892779
2022	33111.789586574494