Quarter	Millions of US Dollars
1971-01-01	46
1971-04-01	31
1971-07-01	31
1972-04-01	32
1973-04-01	14
1973-07-01	41
1973-10-01	35
1974-01-01	32
1974-04-01	92
1974-10-01	173
1975-01-01	417
1975-04-01	443
1975-07-01	231
1975-10-01	456
1976-01-01	766
1976-04-01	729
1976-07-01	220
1976-10-01	372
1977-01-01	603
1977-04-01	566
1977-07-01	340
1977-10-01	447
1978-01-01	493
1978-04-01	632
1978-07-01	815
1978-10-01	811
1979-01-01	1286
1979-04-01	1185
1979-07-01	1001
1979-10-01	274
1980-01-01	299
1980-04-01	447
1980-07-01	866
1980-10-01	1058
1981-01-01	420
1981-04-01	664
1981-07-01	1640
1981-10-01	921
1982-01-01	1170
1982-04-01	800
1982-07-01	1151
1982-10-01	1499
1983-01-01	2491
1983-04-01	2827
1983-07-01	1739
1983-10-01	2764
1984-01-01	3967
1984-04-01	2904
1984-07-01	3176
1984-10-01	2523
1985-01-01	5034
1985-04-01	3365
1985-07-01	4550
1985-10-01	4065
1986-01-01	3994
1986-04-01	7627
1986-07-01	6709
1986-10-01	7669
1987-01-01	6935
1987-04-01	10450
1987-07-01	14330
1987-10-01	4105
1988-01-01	5958
1988-04-01	8243
1988-07-01	17406
1988-10-01	7704
1989-01-01	19601
1989-04-01	29711
1989-07-01	14931
1989-10-01	19491
1990-01-01	10401
1990-04-01	185
1990-07-01	15500
1990-10-01	11229
1991-01-01	11819
1991-04-01	10500
1991-07-01	12273
1991-10-01	9212
1992-01-01	2393
1992-04-01	-195
1992-07-01	-5304
1992-10-01	3149
1993-01-01	-14374
1993-04-01	-18870
1993-07-01	674
1993-10-01	-2394
1994-01-01	-756
1994-04-01	-1802
1994-07-01	-162
1994-10-01	-4492
1995-01-01	-1322
1995-04-01	3511
1995-07-01	-9752
1995-10-01	2610
1996-01-01	2387
1996-04-01	4969
1996-07-01	7084
1996-10-01	3414
1997-01-01	2904
1997-04-01	-1667
1997-07-01	8830
1997-10-01	-9628
1998-01-01	-7919
1998-04-01	-8334
1998-07-01	-3031
1998-10-01	-1638
1999-01-01	-332
1999-04-01	3226
1999-07-01	6516
1999-10-01	-7590
2000-01-01	-12124
2000-04-01	-817
2000-07-01	-8116
2000-10-01	-5921
2001-01-01	-5436
2001-04-01	889
2001-07-01	-6436
2001-10-01	-1168
2002-01-01	-7797
2002-04-01	3186
2002-07-01	-6221
2002-10-01	-10345
2003-01-01	-3696
2003-04-01	-1779
2003-07-01	-4596
2003-10-01	7401
2004-01-01	5551
2004-04-01	9876
2004-07-01	671
2004-10-01	-1643
2005-01-01	5046
2005-04-01	-3010
2005-07-01	2947
2005-10-01	-2627
2006-01-01	11872
2006-04-01	7188
2006-07-01	7787
2006-10-01	9633
2007-01-01	6060
2007-04-01	9646
2007-07-01	-1286
2007-10-01	10363
2008-01-01	2944
2008-04-01	9648
2008-07-01	-4605
2008-10-01	-3750
2009-01-01	-1971
2009-04-01	-9102
2009-07-01	1154
2009-10-01	-3689
2010-01-01	-2043
2010-04-01	-20009
2010-07-01	11031
2010-10-01	-2440
2011-01-01	2040
2011-04-01	-15685
2011-07-01	-952
2011-10-01	-5465
2012-01-01	15123
2012-04-01	-3239
2012-07-01	12568
2012-10-01	976
2013-01-01	8699
2013-04-01	8830
2013-07-01	17376
2013-10-01	12686
2014-01-01	1770
2014-04-01	13743
2014-07-01	18043
2014-10-01	8425
2015-01-01	3944
2015-04-01	4629
2015-07-01	8861
2015-10-01	14192
2016-01-01	15786
2016-04-01	8250
2016-07-01	2188
2016-10-01	8479
2017-01-01	18534
2017-04-01	13397
2017-07-01	45908
2017-10-01	15000
2018-01-01	1209
2018-04-01	8519