Quarter	Millions of US Dollars
1972-10-01	45
1973-01-01	15
1981-07-01	30
1982-10-01	50
1983-01-01	21
1983-07-01	21
1984-04-01	150
1984-07-01	27
1984-10-01	4
1985-01-01	297
1985-04-01	162
1985-07-01	283
1986-04-01	30
1986-07-01	53
1986-10-01	-180
1987-01-01	114
1987-04-01	170
1987-07-01	83
1987-10-01	-25
1988-01-01	166
1988-04-01	120
1988-07-01	150
1989-01-01	486
1989-04-01	153
1989-10-01	439
1990-01-01	111
1990-07-01	537
1990-10-01	227
1991-01-01	1399
1991-04-01	708
1991-07-01	-48
1991-10-01	377
1992-01-01	547
1992-04-01	809
1992-07-01	506
1992-10-01	613
1993-01-01	967
1993-04-01	761
1993-07-01	728
1993-10-01	1542
1994-01-01	-271
1994-04-01	340
1994-07-01	1200
1994-10-01	1868
1995-01-01	189
1995-04-01	-507
1995-07-01	989
1995-10-01	750
1996-01-01	1991
1996-04-01	-59
1996-07-01	1431
1996-10-01	354
1997-01-01	-59
1997-04-01	-548
1997-07-01	-234
1997-10-01	2390
1998-01-01	3457
1998-04-01	-539
1998-07-01	-411
1998-10-01	-519
1999-01-01	1453
1999-04-01	-505
1999-07-01	75
1999-10-01	-677
2000-01-01	1805
2000-04-01	183
2000-07-01	-66
2000-10-01	-285
2001-01-01	-302
2001-04-01	93
2001-07-01	409
2001-10-01	820
2002-01-01	4813
2002-04-01	-31
2002-07-01	-226
2002-10-01	-895
2003-01-01	9057
2003-04-01	1218
2003-07-01	98
2003-10-01	-544
2004-01-01	-289
2004-04-01	2181
2004-07-01	-542
2004-10-01	-1200
2005-01-01	192
2005-04-01	3411
2005-07-01	-1461
2005-10-01	-346
2006-01-01	5265
2006-04-01	6506
2006-07-01	-1912
2006-10-01	5021
2007-01-01	7494
2007-04-01	8493
2007-07-01	-2515
2007-10-01	-5531
2008-01-01	-4599
2008-04-01	7278
2008-07-01	-3950
2008-10-01	4840
2009-01-01	7585
2009-04-01	14909
2009-07-01	3658
2009-10-01	-11270
2010-01-01	1133
2010-04-01	45922
2010-07-01	7072
2010-10-01	26354
2011-01-01	2843
2011-04-01	12648
2011-07-01	-979
2011-10-01	9174
2012-01-01	-15568
2012-04-01	-19551
2012-07-01	-11210
2012-10-01	-2243
2013-01-01	-3581
2013-04-01	-12617
2013-07-01	-6050
2013-10-01	453
2014-01-01	-1068
2014-04-01	1511
2014-07-01	678
2014-10-01	2882
2015-01-01	-3077
2015-04-01	7176
2015-07-01	319
2015-10-01	-8990
2016-01-01	-12395
2016-04-01	-19475
2016-07-01	-12277
2016-10-01	-4577
2017-01-01	-2289
2017-04-01	-11742
2017-07-01	-5928
2017-10-01	3214
2018-01-01	7817
2018-04-01	2933