Year	current US$
1977	2477139.16
1978	3074231.64
1979	2965558.98
1980	3947651.28
1981	4460799.12
1982	4845289.14
1983	5303920.34
1984	5771881.81999998
1985	6329964.38000002
1986	7168545.75999998
1987	7775264.12
1988	7798988.17111111
1989	8876269.34962963
1990	9796153.55281481
1991	10571870.8284
1992	11303651.7137926
1993	11920238.0299407
1994	12628020.0467407
1995	13020309.2448889
1996	13631172.7539111
1997	14259204.6843111
1998	15359259.2592593
1999	15310740.7407408
2000	14707592.5925926
2001	15754833.3333334
2002	15263296.2962963
2003	15814746.2962963
2004	16693348.1481481
2005	16763801.8518519
2006	18762375.925926
2007	20087961.1111111
2008	21992640.7407408
2009	23770925.925926
2010	24219259.2592593
2011	24523888.8888889
2012	23823333.3333334
2013	23939444.4444445
2014	25178175.925926
2015	26092192.5925926
2016	27755027.7777778
2017	26168385.1851852
2018	27779081.4814815
2019	30103622.2222222
2020	25556283.3333334
2021	27791257.4074074