Year	constant 2015 US$
1960	67175000
1961	85684000
1962	87740000
1963	115274000
1964	106863000
1965	120357000
1966	143313000
1967	143644000
1968	251882000
1969	268824000
1970	296907000
1971	316674000
1972	420357000
1973	461634000
1974	604877000
1975	735169000
1976	845746000
1977	1033379000
1978	1151758000
1979	1274204000
1980	1242850000
1981	1229829000
1982	1498754000
1983	1653334000
1984	1612255000
1985	1715774000
1986	2061348000
1987	1954818000
1988	1994638000
1989	1863923000
1990	2137525000
1991	2117637000
1992	2208140000
1993	1963430000
1994	2192296000
1995	2091319000
1996	2153620000
1997	2285789000
1998	2484500000
1999	2494921000
2000	2249372000
2001	2409902000
2002	2743207000
2003	2848878000
2004	2756213000
2005	3078201000
2006	2971090000
2007	3338841000
2008	3158633000
2009	3734541000
2010	3634444000
2011	3433845000
2012	3444876000
2013	3987552000
2014	3882859000
2015	4277660000
2016	4639389000