Year	constant 2015 US$
1992	9940000
1993	46240000
1994	38000000
1995	40820000
1996	30990000
1997	26560000
1998	35830000
1999	33760000
2000	48240000
2001	99080000
2002	56990000
2003	34550000
2004	60960000
2005	31450000
2006	42040000
2007	25010000
2008	13680000
2009	38700000
2010	39580000
2011	36740000
2012	34260000
2013	31500000
2014	30970000
2015	23340000
2016	32900000
2017	28530000