Year	current US$
1970	3.6617834488408336
1971	4.110677228490141
1972	4.475543897722418
1973	5.297836497371046
1974	7.976777939865406
1975	10.613084993417782
1976	9.44988233016061
1977	11.193085204701001
1978	14.367005575153453
1979	17.890841526462285
1980	19.565531450585826
1981	19.354327377935146
1982	18.842657276045117
1983	17.265069318222803
1984	16.771893757440715
1985	18.292255697180813
1986	22.329147188929852
1987	25.566431998567317
1988	27.66382701562847
1989	29.110038493835617
1990	33.7458852598215
1991	33.28133326973076
1992	33.42164351917423
1993	29.527824949375358
1994	30.84397856257082
1995	29.66241521174868
1996	24.301608253975516
1997	21.574321918145696
1998	20.008522691827213
1999	17.927990283457873
2000	17.75230743890776
2001	19.197300941842776
2002	26.59821403891649
2003	37.759583114909944
2004	42.41910159133329
2005	78.9235575465067
2006	68.86096567230557
2007	60.42848696110505
2008	60.68010584880975
2009	54.373108011557406
2010	53.63827681640996
2011	54.605430436635345
2012	51.92434657593823
2013	50.06146444530234
2014	46.42971004907308
2015	43.25270201167363
2016	41.235363072782505
2017	45.80718939212484
2018	44.154643251309864
2019	45.57864416633932
2020	54.92563692521649
2021	50.411704068036556