Year	current US$
1971	139.45081150011424
1972	144.87872470010626
1973	176.3759220329501
1974	188.68228996281343
1975	184.75828923854624
1976	184.4965404019999
1977	217.2833878392734
1978	282.0867839294218
1979	317.7025005131172
1980	370.3534361672426
1981	302.86304556726697
1982	269.8988252878514
1983	235.4862617198563
1984	179.5889157259198
1985	182.0343270406886
1986	236.795499985704
1987	262.3177144346031
1988	261.79648976795966
1989	249.9009989908903
1990	390.0025915417636
1991	358.45186464829686
1992	361.7241496737454
1993	312.6036474528846
1994	192.37407551580037
1995	222.67009969971318
1996	225.47440025284592
1997	206.77798086477856
1998	244.02508810866038
1999	227.3876444745429
2000	193.35646993176178
2001	207.43628588728524
2002	229.39080825800423
2003	269.9409306384741
2004	294.29069711412643
2005	334.3480411799899
2006	346.9761156315499
2007	400.6988171188518
2008	492.44110853613495
2009	477.09019494946943
2010	492.3755141279984
2011	530.5820674905693
2012	530.4618900748696
2013	547.6208719986904
2014	560.8434521593831
2015	489.9019401513057
2016	496.20099263831884
2017	512.3367235380871
2018	577.6735825416846
2019	553.8392381095902
2020	519.1334555879291
2021	574.6236717605808