Year	current US$
1970	286347.272340426
1971	246488.936170213
1972	295446.218457482
1973	394561.951219512
1974	441965.7
1975	543688.170535714
1976	451725.8625
1977	752735.657142857
1978	968267.3
1979	856897.8
1980	1080171.2625
1981	1116482.8125
1982	2666320.8
1983	1834396.87619048
1984	1901162.37142857
1985	684296.008
1986	2019824.19047619
1987	2058385.16190476
1988	2061642.94285714
1989	2108012.44761905
1990	2195769.71428571
1991	2374491.32380952
1992	2178312.5137394
1993	1660803.73829546
1994	1996614.45277361
1995	3119676.92413793
1996	3255065.37931034
1997	3383880.23448276
1998	4901388.8
1999	2158712.18033069
2000	2167577.0767481
2001	2496099.86153846
2002	2867654.75192308
2003	4216752.16607851
2004	4232235.54934269
2005	4319142.07980474
2006	5452297.24508152
2007	5198734.32905816
2008	9424996.47112637
2009	9478066.71362696
2010	11713957.6505121
2011	13889045.7045664
2012	16457438.4748382
2013	14091465.8688864
2014	23317515.2128556
2015	21844345.445895
2016	17474470.9588934
2017	22435044.9443631
2018	11907671.1116555