Year	constant 2015 US$
1968	1633.1702051668221
1969	1575.527066118364
1970	1735.8249382022072
1971	1707.6362098752172
1972	1653.1593429037073
1973	1560.2114232795575
1974	1713.9156822559366
1975	1522.868768741657
1976	1538.1512847810168
1977	1509.3302813030245
1978	1495.905041406021
1979	1526.6675425334984
1980	1544.3399909618456
1981	1522.4871038736717
1982	1448.5428722814172
1983	1444.0730198403267
1984	1377.2114212672961
1985	1356.868762639585
1986	1380.8188184796202
1987	1368.1919929425349
1988	1363.462095438802
1989	1403.38857498241
1990	1346.8632218442083
1991	1345.0219554944176
1992	1321.1104257184645
1993	1335.297387979909
1994	1248.2643442426815
1995	1333.6907104256763
1996	1440.0926780464374
1997	1347.575817447108
1998	1355.0923815081276
1999	1369.8538018790607
2000	1271.8669440314716
2001	1203.4546330810006
2002	1247.540701809831
2003	1303.2082894023617
2004	1334.7232754028942
2005	1411.1168163343198
2006	1568.9614568950692
2007	1510.258829205349
2008	1482.1845761859556
2009	1465.8237001489913
2010	1426.368552977452
2011	1420.6352118215564
2012	1430.8498582046138
2013	1450.3457227233398
2014	1462.2788151057737
2015	1516.9949515115868
2016	1509.6797561717103
2017	1569.5718449096476
2018	1616.3556428816628
2019	1610.0238431576743
2020	1560.3033102248144
2021	1527.07525094359
2022	1602.954310509392
2023	1624.0326616316358