Year	constant 2015 US$
1960	290.73323233317967
1961	244.5934101726624
1962	260.16238277169424
1963	265.3398634402186
1964	274.0744900355505
1965	277.18795146051616
1966	283.1420823706666
1967	314.2932544655516
1968	306.0751422658216
1969	295.26360461893364
1970	350.71277818514994
1971	351.87235066972005
1972	329.6031110295183
1973	353.0736506132947
1974	342.02420974074465
1975	336.2171917883757
1976	355.18595399237654
1977	386.19174795200917
1978	371.9538718167332
1979	369.1874239406932
1980	357.68313409371837
1981	385.2952783998804
1982	371.9972240448671
1983	375.6770063654194
1984	367.2662326071219
1985	401.76720680813474
1986	407.1173263693539
1987	419.85605397239954
1988	431.43729811100934
1989	428.97141533603394
1990	435.0709430305308
1991	447.74485725564955
1992	440.59185674793025
1993	427.06899798723816
1994	408.419316193019
1995	354.11618088360126
1996	325.91191636342745
1997	321.08969069596066
1998	330.12893068730057
1999	319.13580076384
2000	310.0067109370752
2001	308.64519904572666
2002	313.4864058798925
2003	300.0861529733836
2004	303.1196700157275
2005	294.7387733866606
2006	299.7691208207114
2007	298.93666042186493
2008	300.84134924099504
2009	296.84709487161666
2010	297.79172709311035
2011	299.01717566519153
2012	301.4813192948214
2013	305.29083523866035
2014	307.7655313012547
2015	289.35962720612906
2016	282.97596658051054
2017	277.9598030515235
2018	274.1319084708545
2019	270.13727739969823
2020	263.3609886945764
2021	264.36483292563656
2022	262.18480466159656
2023	262.1657056468602