Year	constant 2010 US$
1988	560.502613972697
1989	550.400887092371
1990	537.967867125115
1991	522.934827075214
1992	490.739291271519
1993	473.096576614882
1994	460.558854210891
1995	466.867733557581
1996	476.791883915374
1997	480.363963142772
1998	483.033163372247
1999	486.258346322732
2000	485.905155269061
2001	495.931073889312
2002	500.212037280968
2003	508.686379507252
2004	525.592930958425
2005	545.144001876052
2006	560.037426292794
2007	579.705686877248
2008	597.98999158382
2009	612.663375480015
2010	638.231008539885
2011	643.902576950626
2012	648.85203625587
2013	671.952427102988
2014	693.897925238183
2015	696.303937844149
2016	699.811336643378
2017	715.988309757275
2018	732.278228157222