Year	constant 2015 US$
1975	3102.76513671875
1976	3645.27783203125
1977	4310.033203125
1978	4769.84326171875
1979	5013.43603515625
1980	5240.50244140625
1981	5242.2490234375
1982	5775.85888671875
1983	6144.7861328125
1984	6338.97216796875
1985	6632.650390625
1986	6670.71484375
1987	6957.91552734375
1988	7607.85400390625
1989	8017.9306640625
1990	8551.560546875
1991	9159.38671875
1992	9202.2548828125
1993	8566.01171875
1994	8963.982421875
1995	11361.4921875
1996	11596.8671875
1997	11718.1064453125
1998	12409.8349609375
1999	12784.3212890625
2000	13663.818359375
2001	14266.6865234375
2002	14539.021484375
2003	14989.5947265625
2004	15854.32421875
2005	16238.658203125
2006	16595.35546875
2007	17829.41015625
2008	18815.4375
2009	17121.72265625
2010	17489.525390625
2011	16897.029296875
2012	16180.0927734375
2013	15081.8291015625
2014	15242.5400390625
2015	15809.20703125
2016	16545.427734375
2017	17184.38671875
2018	17845.474609375
2019	18283.681640625
2020	16914.8359375
2021	17690.759765625
2022	18946.505859375
2023	19319.30859375