Year	current US$
1968	61970000.088214904
1969	22819999.9928474
1970	26549999.9523163
1971	32360000.0143051
1972	39870000.362396196
1973	40810000.3004074
1974	31590000.0333786
1975	44370000.4220009
1976	36719999.7901917
1977	35089999.6459484
1978	41539999.9506772
1979	53200001.1242926
1980	51799999.922514
1981	59280001.3516098
1982	55180000.3796816
1983	60380000.5912781
1984	43230000.1978874
1985	39779999.8521805
1986	51999999.567866296
1987	34929999.8283386
1988	44619999.885559104
1989	62690000.1168251
1990	48840000.1227856
1991	38899999.678134896
1992	35559999.5553494
1993	27930000.057444002
1994	21859999.835491203
1995	19419999.837875403
1996	21190000.1168251
1997	33819999.7544289
1998	34109999.2990494
1999	690000.891685486
2000	22040000.2449751
2001	16380000.054836301
2002	16599999.7854233
2003	15180000.2157688
2004	21480000.3170967
2005	13819999.9928474
2006	14969999.9969453
2007	15030000.269413
2008	22840000.063180897
2009	24010000.1096725
2010	25389999.970793698
2011	23020000.1895428
2012	18957102.2540331
2013	24039397.418499
2014	17544756.8446398
2015	18069753.825664498
2016	12217532.858252501
2017	10224681.6977859
2018	6643166.184425349
2019	11467490.9561872
2020	13616105.705499599
2021	16760817.0807362
2022	23495365.977287292