Year	current US$
1977	31840740.7407407
1978	38481481.4814815
1979	51925925.9259259
1980	63303703.7037037
1981	66214814.8148148
1982	75818518.5185185
1983	80544444.4444444
1984	85792592.5925926
1985	88859259.2592593
1986	102374074.074074
1987	113807407.407407
1988	136285185.185185
1989	161903703.703704
1990	152266666.666667
1991	154870370.37037
1992	161688888.888889
1993	162922222.222222
1994	170070370.37037
1995	174511111.111111
1996	186288888.888889
1997	228948148.148148
1998	249014814.814815
1999	239970370.37037
2000	200470370.37037
2001	209458888.888889
2002	214818888.888889
2003	241392481.481481
2004	272195888.888889
2005	291193481.481481
2006	325853296.296296
2007	402115666.666667
2008	430817222.222222
2009	388043629.62963
2010	389200000
2011	376600000
2012	402100000
2013	421367241.33613
2014	444118518.518519
2015	409874074.074074
2016	447144444.444444
2017	433712345.679011