Year US Dollars 1970 402121000 1971 432362000 1972 535905000 1973 573941000 1974 708699000 1975 993880000 1976 1214106000 1977 2485662000 1978 4088903000 1979 4637392000 1980 6108963000 1981 7772614000 1982 7807597000 1983 7692946000 1984 8400085000 1985 8792331000 1986 9418380000 1987 10553610000 1988 10808844000 1989 11376124000 1990 12162489000 1991 12520884000 1992 12262381000 1993 14119671000 1994 18104798000 1995 17001803000 1996 17448114000 1997 18355389000 1998 18544445000 1999 19159134000 2000 17112898000 2001 17744384000 2002 19515997000 2003 19906138000 2004 20562092000 2005 20357305000 2006 20319892000 2007 21043043000 2008 19050114000 2009 13350575000 2010 15045683000 2011 15898725000 2012 16400364000 2013 18618706000 2014 24158307000 2015 27257426000 2016 34083487000