Year	current US$
1971	3956586.48493099
1972	3653509.75247926
1973	4910222.16018776
1974	8644033.35994706
1975	15546791.6603933
1976	20239723.2723286
1977	18476435.2673202
1978	17432887.0145073
1979	17573228.7195547
1980	22311223.5939612
1981	28199206.2852111
1982	30808197.0339225
1983	20354269.1199365
1984	16903064.9522015
1985	20999360.941996
1986	19128333.3118078
1987	18736692.8458014
1988	22328831.4459912
1989	27263956.655882
1990	32624635.3667868
1991	35786818.0853912
1992	31803508.468862
1993	21244759.8659089
1994	19668052.2505623
1995	26090514.2021142
1996	22218605.8774745
1997	17028403.3860868
1998	13738420.3368519
1999	11159253.6897935
2000	13892784.0291634
2001	22491140.9114787
2002	15639273.9738588
2003	13890168.6270796
2004	33708954.2067889
2005	37119387.0267189
2006	39430365.9439834
2007	45836966.4942647
2008	81426600.7357041
2009	34220197.8051435
2010	56783089.8434202
2011	71750218.1336529
2012	51437219.0498902
2013	40948294.0671785
2014	61298955.79577
2015	32241979.6319596
2016	16180389.0418563
2017	35609206.5507845
2018	48563862.3510297
2019	23021807.4868586
2020	16592970.2110987
2021	31282628.6876271