Year	constant 2015 US$
1970	16762.147787399386
1971	16409.461201595303
1972	17315.470687038847
1973	18689.629066017755
1974	19224.67048934179
1975	16635.558976509597
1976	20625.556033867426
1977	22180.020922063828
1978	21952.408264088746
1979	21679.835394112586
1980	21264.155043303024
1981	19342.24688577684
1982	17259.38856220746
1983	17736.003954608324
1984	17981.74080082512
1985	16528.486185966485
1986	16136.293878813029
1987	17189.310102176092
1988	17754.330686169847
1989	17213.10838266584
1990	17383.985105432297
1991	18686.255061551336
1992	19251.229073239138
1993	20998.514987137478
1994	20257.56721433177
1995	20377.69899754036
1996	20550.626001896067
1997	20540.680158356186
1998	20889.517096455093
1999	21169.232080679176
2000	21686.218061286647
2001	21653.749212717245
2002	21838.537349830032
2003	22320.785401587997
2004	22297.61285964653
2005	21999.61650284392
2006	21756.44307693
2007	21986.06068935472
2008	21890.42781155577
2009	21131.172669679425
2010	21425.929438786505
2011	21879.183341525248
2012	22456.564355392962
2013	22983.75373560596
2014	23078.882145246844
2015	22850.6653959938
2016	22847.34603537302
2017	22950.212141415945
2018	22994.15207446246
2019	23384.7592873445
2020	22550.95263633045
2021	23359.688205264807
2022	24353.07326091146
2023	24734.342069295177