Year	current US$
1960	1.2090755871983252
1961	3.5601579072002174
1962	3.4078958206457095
1963	3.4266875354691426
1964	2.8455673511700823
1965	3.480220791593907
1966	3.6431757289105504
1967	2.940080383945749
1968	3.0795661013754922
1969	2.6148006816662464
1970	2.604040077298927
1971	2.257652105657596
1972	2.247362795275518
1973	2.359789620824093
1974	2.6403311505612006
1975	3.156253955055142
1976	3.029190090061485
1977	2.83277252577153
1978	3.487385508013026
1979	4.223909143014636
1980	5.023527676813699
1981	5.366465663452561
1982	5.823115006046026
1983	6.227188222575531
1984	6.444570915266872
1985	7.470273101252241
1986	8.073810395299674
1987	9.44430454023893
1988	9.539771941257412
1989	10.416925905815118
1990	11.194741180438243
1991	12.625341403117146
1992	11.418117625598478
1993	11.00875341024157
1994	11.780445687735698
1995	12.541234897789929
1996	14.268819150069268
1997	10.192264670286304
1998	10.146270304600675
1999	10.957586356445871
2000	8.937307606283916
2001	10.532406840534282
2002	9.090570884824366
2003	10.69976222169542
2004	12.004325090002043
2005	11.491603544939073
2006	12.449537830706092
2007	11.42392512809962
2008	15.328976272635527
2009	14.44062152245553
2010	16.346726805147128
2011	16.682288920778774
2012	16.65421658239797
2013	16.913564656201434
2014	16.19802078280439
2015	16.30717952894516
2016	17.825823916194114
2017	13.402183437503114
2018	16.13648552756601
2019	13.42256730478292
2020	18.778708262585425
2021	18.141522114980784
2022	19.651499853391346