Year	constant 2015 US$
1960	583.6489680111046
1961	601.5881672511997
1962	568.5629994525628
1963	553.828340194447
1964	554.2780247337471
1965	548.1902908025742
1966	540.134010034164
1967	553.0932212764609
1968	548.2533678734134
1969	573.6965844463208
1970	574.0636177062028
1971	568.4887236013129
1972	557.2944763535103
1973	556.8854858403869
1974	580.7094667436378
1975	571.6697628512238
1976	593.776778049133
1977	610.140243364448
1978	611.2779909436825
1979	590.1301465036614
1980	557.877977651788
1981	543.4712301896753
1982	579.0879675037914
1983	526.172596368677
1984	569.5704495334843
1985	585.0904821196411
1986	598.8575833558864
1987	562.3233812367971
1988	562.9772821248234
1989	560.0150989393875
1990	531.3860051866243
1991	512.2518399944378
1992	464.33546331898225
1993	451.19993517344443
1994	458.6545235835427
1995	478.343894844851
1996	447.35063066455103
1997	458.13383528211324
1998	466.6341085394654
1999	470.168358919745
2000	445.8032929844214
2001	455.338380225211
2002	461.4980856468225
2003	426.15958084043206
2004	442.0152360506393
2005	436.10026510064574
2006	447.8081065033808
2007	459.74606635342866
2008	459.56245720012924
2009	488.38802503845807
2010	500.5292773550333
2011	513.5942667503231
2012	534.8835626113553
2013	338.1657057744852
2014	338.7003848430515
2015	351.8797547695543
2016	362.21833116788395
2017	371.6031310363132
2018	378.2630778059262
2019	381.4140463549479
2020	375.2169240732808
2021	370.98037300953575
2022	364.6907533807286
2023	357.41141092809