Quarter	Millions of US Dollars
1972-01-01	0
1972-04-01	0
1972-07-01	0
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	30
1980-10-01	30
1981-01-01	30
1981-04-01	30
1981-07-01	50
1981-10-01	50
1982-01-01	50
1982-04-01	100
1982-07-01	50
1982-10-01	160
1983-01-01	270
1983-04-01	228
1983-07-01	258
1983-10-01	163
1984-01-01	53
1984-04-01	180
1984-07-01	238
1984-10-01	578
1985-01-01	679
1985-04-01	622
1985-07-01	614
1985-10-01	386
1986-01-01	398
1986-04-01	463
1986-07-01	508
1986-10-01	466
1987-01-01	414
1987-04-01	403
1987-07-01	374
1987-10-01	367
1988-01-01	423
1988-04-01	468
1988-07-01	371
1988-10-01	360
1989-01-01	308
1989-04-01	211
1989-07-01	353
1989-10-01	338
1990-01-01	273
1990-04-01	194
1990-07-01	52
1990-10-01	0
1991-01-01	0
1991-04-01	0
1991-07-01	0
1991-10-01	0
1992-01-01	0
1992-04-01	0
1992-07-01	0
1992-10-01	0
1993-01-01	20
1993-04-01	320
1993-07-01	335
1993-10-01	335
1994-01-01	315
1994-04-01	15
1994-07-01	0
1994-10-01	89
1995-01-01	89
1995-04-01	89
1995-07-01	194
1995-10-01	105
1996-01-01	105
1996-04-01	105
1996-07-01	0
1996-10-01	0
1997-01-01	0
1997-04-01	85
1997-07-01	143
1997-10-01	143
1998-01-01	143
1998-04-01	58
1998-07-01	0
1998-10-01	9
1999-01-01	19
1999-04-01	14
1999-07-01	40
1999-10-01	43
2000-01-01	66
2000-04-01	68
2000-07-01	54
2000-10-01	532
2001-01-01	200
2001-04-01	213
2001-07-01	314
2001-10-01	314
2002-01-01	322
2002-04-01	325
2002-07-01	246
2002-10-01	42
2003-01-01	200
2003-04-01	288
2003-07-01	291
2003-10-01	576
2004-01-01	948
2004-04-01	1205
2004-07-01	1665
2004-10-01	1632
2005-01-01	1604
2005-04-01	1941
2005-07-01	1473
2005-10-01	1743
2006-01-01	1556
2006-04-01	865
2006-07-01	1440
2006-10-01	1696
2007-01-01	1409
2007-04-01	1413
2007-07-01	887
2007-10-01	134
2008-01-01	1599
2008-04-01	1607
2008-07-01	1546
2008-10-01	2129
2009-01-01	1206
2009-04-01	1241
2009-07-01	1357
2009-10-01	754
2010-01-01	429
2010-04-01	1055
2010-07-01	896
2010-10-01	1122
2011-01-01	1053
2011-04-01	906
2011-07-01	1308
2011-10-01	1097
2012-01-01	2078
2012-04-01	2577
2012-07-01	2176
2012-10-01	5771
2013-01-01	2668
2013-04-01	1800
2013-07-01	1802
2013-10-01	710
2014-01-01	92
2014-04-01	1012
2014-07-01	1028
2014-10-01	1942
2015-01-01	1933
2015-04-01	1679
2015-07-01	1678
2015-10-01	2930
2016-01-01	3421
2016-04-01	2719
2016-07-01	2772
2016-10-01	1628
2017-01-01	4088
2017-04-01	5004
2017-07-01	5640
2017-10-01	5081
2018-01-01	4558
2018-04-01	3123