Year	current US$
1970	20.650600136272995
1971	23.24155348047993
1972	26.526655617694228
1973	31.92610709585042
1974	46.1257167536474
1975	55.73861377854909
1976	76.00008904763392
1977	69.14459520163882
1978	95.13613924035471
1979	101.96990093995933
1980	125.46524189164671
1981	127.63012568938397
1982	115.11682244135012
1983	115.72602922712097
1984	110.03508632780103
1985	98.2476596695954
1986	121.46643122967278
1987	131.65060175889448
1988	127.19605523202827
1989	141.74949539044647
1990	184.42595276913445
1991	161.23931631173346
1992	147.71786052227282
1993	156.3023834869831
1994	175.89566052459452
1995	164.95170573373684
1996	159.38371437513635
1997	142.20052908581934
1998	126.47616674531017
1999	113.02229674083672
2000	105.97088283477137
2001	104.39796751744193
2002	113.07473558714523
2003	112.46101492831151
2004	121.0221629411083
2005	127.66750836791466
2006	137.5378069113347
2007	172.93389887724757
2008	219.0333775426937
2009	208.03153774178466
2010	226.26914625853715
2011	217.952391621023
2012	209.62990919678347
2013	208.94811161255785
2014	176.07506337324867
2015	151.58945794350348
2016	142.36563236377867
2017	172.04028331067613
2018	183.6652221657616
2019	185.36928712237474
2020	254.8745405156314
2021	249.6159457788634