Year	constant 2015 US$
1980	384963000
1981	647558000
1982	672766000
1983	229797000
1984	454374000
1985	553284000
1986	494399000
1987	468894000
1988	447765000
1989	928589000
1990	1328125000
1991	1655477000
1992	1839273000
1993	1877252000
1994	1903855000
1995	1745251000
1996	1590870000
1997	1771274000
1998	1964280000
1999	1982166000
2000	1944753000
2001	2795404000
2002	2514925000
2003	2312303000
2004	2514250000
2005	2988811000
2006	3596264000
2007	4300792000
2008	5339275000
2009	5289218000
2010	5016936000
2011	3351183000
2012	1768619000
2013	1966464000
2014	1577013000
2015	1396740000
2016	4263392000