Year	constant 2015 US$
1975	844.8159728114761
1976	895.0844856852744
1977	926.3038795774245
1978	1039.453229411609
1979	1165.1965341546718
1980	1104.2592098042492
1981	1124.6283804860807
1982	1117.8848105297618
1983	1135.1634860469865
1984	1186.848853604706
1985	1496.3190939560197
1986	1664.0549288167763
1987	1825.506837212196
1988	2097.7127293610256
1989	2131.300816174739
1990	2377.930465072809
1991	2535.050978355868
1992	2550.5492194014614
1993	2710.242539346657
1994	2327.264929703469
1995	2536.978205501758
1996	2793.691492164113
1997	3070.469955479738
1998	2924.8023516424637
1999	3175.1753846802885
2000	3051.3670481320078
2001	3073.064646710118
2002	2678.0006824586367
2003	2461.7103675349354
2004	2484.6179649503197
2005	2947.6878025326705
2006	3191.6846443912914
2007	3465.055604918106
2008	3792.898615556264
2009	3479.4185719756247
2010	3790.1255943749916
2011	4449.98405329822
2012	4408.542721964408
2013	4598.390427581268
2014	4926.081541752758
2015	4548.211465813512
2016	4706.660699981889
2017	4549.784814492968
2018	4356.955419319586
2019	4629.617790699286
2020	4551.852536950522
2021	4623.115027886248