Year US Dollars, Sum Over Component Sub-periods 1971-01-01 1180520000.0000000 1972-01-01 1232130000.0000000 1973-01-01 5111080000.0000000 1974-01-01 10618970000.0000000 1975-01-01 4906010000.0000000 1976-01-01 3880420000.0000000 1977-01-01 4173020000.0000005 1978-01-01 9262300000.0000000 1979-01-01 -5792590000.0000000 1980-01-01 -15753420000.0000000 1981-01-01 -5216240000.0000000 1982-01-01 5503020000.0000000 1983-01-01 4313850000.0000000 1984-01-01 9194410000.0000000 1985-01-01 17973250000.0000000 1986-01-01 38799560000.0000000 1987-01-01 44530680000.0000000 1988-01-01 54141380000.0000000 1989-01-01 57192520000.0000000 1990-01-01 46624260000.0000000 1991-01-01 -23937890000.0000000 1992-01-01 -22724450000.0000000 1993-01-01 -18984880000.0000000 1994-01-01 -30727980000.0000000 1995-01-01 -29643960000.0000000 1996-01-01 -14216040000.0000000 1997-01-01 -10538910000.0000000 1998-01-01 -16041850000.0000000 1999-01-01 -28275670000.0000000 2000-01-01 -32433040000.0000000 2001-01-01 -120570000.0000000 2002-01-01 41085030000.0000000 2003-01-01 46909490000.0000000 2004-01-01 127561470000.0000000 2005-01-01 139884650000.0000000 2006-01-01 182514350000.0000000 2007-01-01 249085150000.0000000 2008-01-01 226110370000.0000000 2009-01-01 198343860000.0000000 2010-01-01 211750880000.0000000 2011-01-01 247213700000.0000000 2012-01-01 255553750000.0000000 2013-01-01 273803190000.0000000