Quarter Millions of US Dollars 1971-10-01 15 1972-04-01 32 1972-07-01 18 1974-10-01 24 1975-01-01 7 1975-07-01 40 1975-10-01 6 1976-07-01 32 1976-10-01 116 1977-04-01 47 1977-07-01 33 1977-10-01 121 1978-01-01 199 1978-04-01 176 1978-07-01 100 1978-10-01 181 1979-01-01 281 1979-04-01 100 1979-07-01 19 1979-10-01 165 1980-01-01 80 1980-04-01 68 1980-07-01 38 1981-04-01 236 1981-10-01 112 1982-01-01 55 1982-04-01 135 1982-07-01 178 1982-10-01 47 1983-01-01 129 1983-04-01 194 1983-07-01 121 1983-10-01 18 1984-01-01 32 1984-04-01 52 1984-07-01 122 1984-10-01 42 1985-01-01 63 1985-04-01 171 1985-07-01 54 1985-10-01 -241 1986-01-01 36 1986-04-01 98 1986-07-01 94 1986-10-01 -79 1987-01-01 459 1987-04-01 -28 1987-07-01 -240 1987-10-01 493 1988-01-01 -100 1988-04-01 508 1988-07-01 -333 1988-10-01 -54 1989-01-01 29 1989-04-01 -130 1989-07-01 -5 1989-10-01 -11 1990-04-01 -155 1990-07-01 179 1990-10-01 669 1991-01-01 1146 1991-04-01 -216 1991-07-01 676 1991-10-01 1740 1992-01-01 2029 1992-04-01 3780 1992-07-01 2277 1992-10-01 3487 1993-01-01 3852 1993-04-01 2031 1993-07-01 -220 1993-10-01 175 1994-01-01 1455 1994-04-01 2689 1994-07-01 3471 1994-10-01 225 1995-01-01 1385 1995-04-01 -113 1995-07-01 -228 1995-10-01 -805 1996-01-01 1414 1996-04-01 -551 1996-07-01 -273 1996-10-01 222 1997-01-01 -102 1997-04-01 -650 1997-07-01 -1000 1997-10-01 -3583 1998-01-01 -1350 1998-04-01 1080 1998-07-01 -170 1998-10-01 -1689 1999-01-01 -326 1999-07-01 -60 1999-10-01 -386 2000-01-01 -1753 2000-04-01 -141 2000-07-01 -883 2000-10-01 -1486 2001-01-01 -1265 2001-04-01 4116 2001-07-01 -407 2001-10-01 -457 2002-01-01 877 2002-04-01 -1354 2002-07-01 -619 2002-10-01 -142 2003-01-01 6650 2003-04-01 3541 2003-07-01 -690 2003-10-01 -1506 2004-01-01 1331 2004-04-01 -1102 2004-07-01 -2032 2004-10-01 -89 2005-01-01 -19 2005-04-01 -1122 2006-01-01 -1000 2006-04-01 -48 2006-07-01 -8183 2006-10-01 376 2007-01-01 -2112 2007-04-01 -702 2007-07-01 -6720 2007-10-01 -442 2008-04-01 -197 2008-07-01 -7512 2008-10-01 -303 2009-01-01 2325 2009-04-01 -4405 2009-07-01 100 2010-01-01 1643 2010-04-01 1000 2010-10-01 2000 2011-01-01 10723 2011-04-01 -2191 2011-07-01 800 2012-01-01 1127 2012-04-01 3032 2012-07-01 -2033 2013-01-01 411 2013-04-01 -1000 2013-07-01 387 2013-10-01 3000 2014-01-01 -342 2014-04-01 2651 2014-07-01 1417 2014-10-01 549 2015-01-01 -123 2015-04-01 2901 2015-07-01 -163 2015-10-01 -3497 2016-01-01 -5131 2016-04-01 4291 2016-07-01 -152 2016-10-01 -130 2017-01-01 -1192 2017-04-01 792 2017-07-01 2246 2017-10-01 -331 2018-01-01 -576 2018-04-01 -2981