Year	current US$
1970	437.292884178175
1971	367.691577249397
1972	384.591486414735
1973	763.127678933949
1974	824.061514704695
1975	1154.05714285714
1976	950.4
1977	1671.89268292683
1978	1687.1234521576
1979	2182.50619136961
1980	2566.41372093023
1981	2348.64
1982	6024
1983	2160.86745114974
1984	1294.16170212766
1985	919.285714285714
1986	964.542857142857
1987	964.542857142857
1988	1122.94285714286
1989	1122.94285714286
1990	4325.14285714286
1991	4903.83157894737
1992	3383.62593473635
1993	4588.96294908225
1994	5943.44309845078
1995	7793.04373575413
1996	6052.54098413493
1997	8241.25499854048
1998	7891.94783080054
1999	7053.09296026272
2000	6741.02858594047
2001	6996.15423197492
2002	6518.01458128079
2003	7226.81848766278
2004	7807.17984616714
2005	7942.68617939384
2006	11924.8890281044
2007	12847.5990223545
2008	14242.221112204
2009	13529.9548905884
2010	32292.0767759666
2011	28214.0859776356
2012	28285.7456403659
2013	38762.9342426596
2014	50214.276899536
2015	39108.2321074596
2016	53708.3433674603
2017	45883.7153630107
2018	30866.3859477738
2019	28218.8578656124
2020	38523.4875426553
2021	30821.3480225693