Year	constant 2015 US$
1977	8394310.637610972
1978	11587405.768765127
1979	9606420.620460043
1980	12283916.412429372
1981	14463904.32203389
1982	16671029.416868431
1983	16996670.417675532
1984	15911199.327078277
1985	17991685.529661004
1986	18760561.347861167
1987	19873169.62368845
1988	21890337.032889415
1989	23210993.145681992
1990	23910018.15980629
1991	24869552.058111373
1992	26775564.971751407
1993	27173738.90234059
1994	24556234.866828084
1995	25117594.834543984
1996	26631961.2590799
1997	27297760.290556896
1998	31893079.096045196
1999	26377391.041162226
2000	28329096.045197736
2001	26677653.34947538
2002	23668502.824858755
2003	25913942.695722353
2004	27735098.87005649
2005	27023607.748184014
2006	28472699.757869244
2007	27323870.05649717
2008	23988347.457627114
2009	23355185.633575458
2010	23015758.67635189
2011	21664578.288942687
2012	22878682.40516545
2013	23629338.17594834
2014	23688085.14931396
2015	21566666.666666664
2016	18857778.450363193
2017	16866908.79741727
2018	16201109.765940271
2019	14621468.92655367
2020	15293795.399515739
2021	14007889.426957225
2022	16233746.97336562
2023	16396933.010492336
