Year	current US$
1970	158.6686583659263
1971	179.62807444577163
1972	217.79764590787624
1973	260.0321755727392
1974	225.78978600814793
1975	325.236330529439
1976	293.86541088262163
1977	285.5588667362976
1978	300.40853718350945
1979	343.46820314197765
1980	516.2065394729732
1981	725.7125812881787
1982	813.9629601352456
1983	640.8530157806358
1984	608.9334153136648
1985	571.8884416166358
1986	560.7813243950975
1987	599.2452579674174
1988	415.2894185771399
1989	306.0228351341894
1990	276.3695334334459
1991	419.4728788257311
1992	456.61528059808614
1993	290.5265974256679
1994	210.01793501886618
1995	22.833534913738387
1996	34.522602970310324
1997	104.43408440965351
1998	180.02630078445006
1999	120.0808088833892
2000	4.861780405713091
2001	75.64845371844727
2002	102.73617135015091
2003	204.8030376735231
2004	194.86125401124073
2005	327.8128844501733
2006	466.3577496586573
2007	609.196567889852
2008	765.4212339203204
2009	939.1709803006391
2010	1052.6372309478256
2011	940.9354318610184
2012	1516.6817193585857
2013	1938.4833479307863
2014	2140.11465989952
2015	1473.5280938141977
2016	1169.753258897165
2017	866.1917614024817
2018	1044.4033854583884
2019	877.0679418732346
2020	770.8113305629713
2021	1079.5371809839035