Year	current US$
1970	2420.153447496638
1971	2781.0343246569064
1972	3309.8817827225907
1973	4387.974388132962
1974	4865.595712626102
1975	5344.049704201656
1976	5702.210021066904
1977	6596.738743672305
1978	8167.824586854322
1979	9669.462234536068
1980	10333.024270249556
1981	8598.929038628565
1982	8303.480522278896
1983	8295.590387218344
1984	7863.416325590999
1985	7966.953727651945
1986	11388.827016318166
1987	14069.971742064996
1988	15243.036933966625
1989	15136.427888332688
1990	19019.043191209163
1991	19773.307338521925
1992	22313.22996243516
1993	21371.87405880473
1994	22642.90963165719
1995	26435.10328738035
1996	25446.25951117497
1997	22429.162330276267
1998	22615.00937979269
1999	22110.41709850506
2000	19549.44184245544
2001	19447.03569440786
2002	20609.381554828586
2003	24783.896385461823
2004	28464.02957220831
2005	28850.872771564227
2006	30794.461706334736
2007	35163.3139253451
2008	38083.934775276786
2009	34858.124861142926
2010	34884.03479191246
2011	39563.81733289573
2012	36959.96893459629
2013	38946.313067057905
2014	40356.48312003692
2015	34656.44190574964
2016	35663.67889296437
2017	37760.33967622767
2018	40854.55597161824
2019	39718.00233425052
2020	39043.097150167414
2021	42982.481891127005