Year	constant 2015 US$
1991	82355.10113566159
1992	82106.88664487167
1993	71634.26057440735
1994	47861.88864712899
1995	36223.55513661388
1996	43651.508445271786
1997	46670.47653477402
1998	40080.58551328808
1999	33683.53757066338
2000	36974.991826776924
2001	36618.591388578716
2002	30997.598630710832
2003	29082.87151029823
2004	27273.131300787398
2005	25510.176973993726
2006	24192.278581463677
2007	25244.549813689988
2008	23127.445272838988
2009	31288.552166761583
2010	32143.969791153384
2011	34177.02001350191
2012	38388.533839527634
2013	34899.59767249339
2014	35564.821839715034
2015	34767.65019445403
2016	32185.932399417332
2017	29518.191279376104
2018	26994.99328988085
2019	21236.293489636773
2020	19808.305833897575
2021	17848.21858695055
2022	17786.185429271423
