Quarter	Millions of US Dollars
1972-10-01	0
1973-01-01	0
1973-04-01	0
1973-07-01	0
1973-10-01	0
1974-01-01	0
1974-04-01	0
1974-07-01	0
1974-10-01	0
1975-01-01	0
1975-04-01	0
1975-07-01	0
1975-10-01	0
1976-01-01	0
1976-04-01	0
1976-07-01	0
1976-10-01	0
1977-01-01	0
1977-04-01	0
1977-07-01	0
1977-10-01	0
1978-01-01	0
1978-04-01	0
1978-07-01	0
1978-10-01	0
1979-01-01	0
1979-04-01	0
1979-07-01	0
1979-10-01	0
1980-01-01	0
1980-04-01	0
1980-07-01	0
1980-10-01	0
1981-01-01	0
1981-04-01	0
1981-07-01	0
1981-10-01	0
1982-01-01	0
1982-04-01	0
1982-07-01	0
1982-10-01	0
1983-01-01	0
1983-04-01	0
1983-07-01	0
1983-10-01	20
1984-01-01	20
1984-04-01	20
1984-07-01	20
1984-10-01	0
1985-01-01	0
1985-04-01	0
1985-07-01	0
1985-10-01	180
1986-01-01	180
1986-04-01	180
1986-07-01	180
1986-10-01	25
1987-01-01	40
1987-04-01	40
1987-07-01	40
1987-10-01	15
1988-01-01	0
1988-04-01	0
1988-07-01	0
1988-10-01	0
1989-01-01	0
1989-04-01	0
1989-07-01	36
1989-10-01	35
1990-01-01	32
1990-04-01	171
1990-07-01	185
1990-10-01	230
1991-01-01	227
1991-04-01	173
1991-07-01	135
1991-10-01	296
1992-01-01	403
1992-04-01	334
1992-07-01	391
1992-10-01	163
1993-01-01	328
1993-04-01	350
1993-07-01	738
1993-10-01	727
1994-01-01	625
1994-04-01	911
1994-07-01	961
1994-10-01	1309
1995-01-01	1633
1995-04-01	1627
1995-07-01	1338
1995-10-01	1229
1996-01-01	1039
1996-04-01	1058
1996-07-01	2950
1996-10-01	3322
1997-01-01	3388
1997-04-01	4833
1997-07-01	3420
1997-10-01	4245
1998-01-01	4759
1998-04-01	3924
1998-07-01	3960
1998-10-01	3549
1999-01-01	3140
1999-04-01	2184
1999-07-01	2497
1999-10-01	2934
2000-01-01	2291
2000-04-01	2354
2000-07-01	2075
2000-10-01	1812
2001-01-01	1469
2001-04-01	1276
2001-07-01	1359
2001-10-01	1446
2002-01-01	3135
2002-04-01	3646
2002-07-01	3473
2002-10-01	3121
2003-01-01	3049
2003-04-01	2990
2003-07-01	3847
2003-10-01	6094
2004-01-01	5041
2004-04-01	4525
2004-07-01	4622
2004-10-01	2683
2005-01-01	2599
2005-04-01	5388
2005-07-01	1805
2005-10-01	1949
2006-01-01	2007
2006-04-01	7038
2006-07-01	3635
2006-10-01	4011
2007-01-01	7105
2007-04-01	22628
2007-07-01	19485
2007-10-01	14559
2008-01-01	9572
2008-04-01	14111
2008-07-01	9956
2008-10-01	11099
2009-01-01	9321
2009-04-01	18151
2009-07-01	22353
2009-10-01	10665
2010-01-01	9184
2010-04-01	6234
2010-07-01	9650
2010-10-01	13415
2011-01-01	31308
2011-04-01	43394
2011-07-01	38123
2011-10-01	47095
2012-01-01	34694
2012-04-01	53447
2012-07-01	52963
2012-10-01	74427
2013-01-01	75282
2013-04-01	49447
2013-07-01	49719
2013-10-01	39832
2014-01-01	43686
2014-04-01	48412
2014-07-01	39723
2014-10-01	46191
2015-01-01	37072
2015-04-01	54395
2015-07-01	63800
2015-10-01	55686
2016-01-01	41702
2016-04-01	32112
2016-07-01	29656
2016-10-01	25205
2017-01-01	24829
2017-04-01	13920
2017-07-01	3076
2017-10-01	5499
2018-01-01	4301
2018-04-01	13395
