Year	constant 2010 US$
1988	639954509.617354
1989	603291292.136132
1990	569014853.709588
1991	551639022.265882
1992	503194434.250622
1993	477893310.781899
1994	306305643.181523
1995	319366822.82776
1996	337152606.136445
1997	338018800.125733
1998	338984568.126092
1999	328843274.983711
2000	327095631.018222
2001	327461956.811461
2002	332690424.951337
2003	334022518.744936
2004	325696932.534943
2005	331025307.709339
2006	338684847.022532
2007	343014151.851729
2008	342681128.403329
2009	358000207.029717
2010	303717384.94056
2011	357667183.581317
2012	382976965.659697
2013	390969528.421291
2014	401626278.770083
2015	419942568.432068
2016	426270013.951662
2017	430599318.780861
2018	435594670.506857