Year	constant 2010 US$
1991	7658.51568636607
1992	7828.15802605574
1993	8038.61179727745
1994	19552.9729790671
1995	19260.2053916745
1996	19156.2934740402
1997	19204.099922781
1998	18898.6609927471
1999	19119.1044505829
2000	19840.5074457508
2001	20129.4323277848
2002	20551.4751981263
2003	20762.2684378066
2004	20514.1598123596
2005	20684.4636295358
2006	20690.2065580321
2007	21007.6614936979
2008	21076.2595325471
2009	20779.9378950037
2010	20799.3246342212
2011	21027.7845930183
2012	21383.142715623
2013	21535.1954863837
2014	21544.7021403109
2015	21846.4603794331
2016	22124.207378508
2017	22389.1833960153
2018	16891.9233439305