Year	constant 2015 US$
1977	4449.300273500878
1978	4637.942366817293
1979	5011.880831927182
1980	5457.715243677601
1981	5560.720861302586
1982	5611.952926130329
1983	5704.411188728239
1984	6242.391001303532
1985	6814.064934689083
1986	7599.851842686256
1987	8150.593040581926
1988	8966.288340540956
1989	9533.528942488669
1990	10086.09706164682
1991	9920.972095343146
1992	10253.949843887776
1993	10806.88613191247
1994	11229.734979339542
1995	11681.556635616615
1996	12207.162330896925
1997	12873.200095805641
1998	12644.290051601549
1999	12878.17930944056
2000	13973.250567209401
2001	14539.421796365152
2002	14649.717457040302
2003	14022.867623904254
2004	14536.621094405407
2005	15901.942822309971
2006	16350.774129037018
2007	16399.646071083436
2008	18178.367390947624
2009	17515.77709011103
2010	17480.228695619076
2011	17696.364851785616
2012	17549.474312952843
2013	18535.983221772247
2014	19892.100818940384
2015	20029.759828880982
2016	20818.342075774326
2017	20865.64824796112
2018	21294.39193204043
2019	21919.781521520108
2020	18581.380657382644
2021	18684.630294034672
2022	20628.686399289327
2023	21292.702560944017