Year	constant 2015 US$
1996	11893.74057207468
1997	11961.10167836186
1998	12146.805229353567
1999	12363.667981018965
2000	12580.998724495666
2001	12117.94549427275
2002	12187.116270102002
2003	12561.31837205071
2004	12909.424788410106
2005	14236.871436372256
2006	15461.716810705962
2007	16144.218316722145
2008	16640.166473664107
2009	16543.802501165734
2010	17311.676997502957
2011	18019.425787644155
2012	18961.49997924856
2013	18471.709896363333
2014	18697.638267850496
2015	19035.139187035435
2016	19064.673175391003
2017	19252.878874599148
2018	19521.244831480726
2019	19544.6572810501
2020	18533.51321446187
2021	18941.984125511084
2022	18913.887797024716