Year US Dollars 1970 -68141046.77519 1971 -61986923.96921 1972 -61777227.72277 1973 -62256663.95065 1974 -99436128.74485 1975 -59993528.95236 1976 -58480763.40503 1977 -84485615.53319 1978 -55387100.36761 1979 -52369461.07784 1980 -68424185.9309 1981 -99910634.99112 1982 -184705312.5 1983 -161486647.47344 1984 -154890958.18977 1985 -163786694.72914 1986 -136184618.7459 1987 -155641898.60835 1988 -192014921.49994 1989 -218934959.34959 1990 -326456841.82088 1991 -288586055.77689 1992 -209909139.85732 1993 -251440651.31948 1994 -293208110.87129 1995 -324416342.41245 1996 -334206765.12625 1997 -180180180.18018 1998 -103326334.40159 1999 -95027981.05898 2000 -309817754.2622 2001 -72116760.46933 2002 206217206.2172 2003 47456469.78491 2004 -80592924.76333 2005 -156323840.31837 2006 -228076778.32141 2007 44483985.76512 2008 -22264537.86436 2009 -128230063.90664 2010 -79602649.00662 2011 213606894.63442 2012 427675318.00077 2013 636869622.94211 2014 1338837070.45244 2015 746600643.22946 2016 1206696681.41593