Year	US Dollars
1970	1172000
1971	1238000
1972	1507000
1973	1693000
1974	4292000
1975	4722000
1976	18516000
1977	24523000
1978	29351000
1979	40110000
1980	43977000
1981	54853000
1982	68942000
1983	85801000
1984	104791000
1985	134215000
1986	166564000
1987	203347000
1988	199821000
1989	174681000
1990	184829000
1991	179474000
1992	187895000
1993	187450000
1994	199633000
1995	211444000
1996	223339000
1997	224515000
1998	232229000
1999	233861000
2000	234497000
2001	244900000
2002	272866000
2003	291527000
2004	305882000
2005	290052000
2006	294926000
2007	289247000
2008	277768000
2009	288365000
2010	280577000
2011	277941000
2012	255676000
2013	151057000
2014	145043000
2015	133679000
2016	159918000