Year	constant 2015 US$
1970	12922.707317859831
1971	12526.836355597363
1972	12123.479583569728
1973	11790.53628810805
1974	11690.188269319833
1975	11744.155174812833
1976	11802.941579199729
1977	12044.74020872154
1978	12059.429238958348
1979	12099.288489658216
1980	12101.24401256124
1981	11925.538033444844
1982	11618.274046747698
1983	11562.487232292693
1984	11800.372088706432
1985	12127.29616139031
1986	12474.818420246027
1987	12855.18776086123
1988	13254.856261679668
1989	13671.78526487026
1990	14098.342037156664
1991	14461.756607582614
1992	13228.332709521022
1993	11334.934237200185
1994	11879.542252814641
1995	12838.3342869718
1996	13755.483519693238
1997	13637.327694399328
1998	13500.558318532114
1999	12423.575767517239
2000	11887.838993393287
2001	12595.465827621478
2002	13211.953910919889
2003	12767.436725064883
2004	13252.354246091949
2005	13757.310240383042
2006	13888.764800935463
2007	14317.001409478866
2008	13717.432457796454
2009	12907.966851773303
2010	12989.661373732839
2011	13879.0892575161
2012	14283.281153190483
2013	13959.274849931231
2014	14705.775811300993
2015	16141.169658333767
2016	16263.499869984786
2017	15669.36572884326
2018	15744.7982137504
2019	15841.878632437467
2020	14597.335037948074
2021	12493.612153170663
2022	12426.97570922805
2023	12480.628289498967