Quarter	Millions of US Dollars
1971-01-01	0
1971-04-01	0
1971-07-01	0
1971-10-01	0
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	37
1981-01-01	34
1981-04-01	32
1981-07-01	8
1981-10-01	0
1982-01-01	0
1982-04-01	0
1982-07-01	0
1982-10-01	0
1983-01-01	20
1983-04-01	20
1983-07-01	74
1983-10-01	72
1984-01-01	64
1984-04-01	107
1984-07-01	61
1984-10-01	63
1985-01-01	55
1985-04-01	15
1985-07-01	7
1985-10-01	3
1986-01-01	55
1986-04-01	74
1986-07-01	203
1986-10-01	210
1987-01-01	159
1987-04-01	137
1987-07-01	0
1987-10-01	6
1988-01-01	6
1988-04-01	5
1988-07-01	371
1988-10-01	608
1989-01-01	576
1989-04-01	561
1989-07-01	288
1989-10-01	175
1990-01-01	224
1990-04-01	233
1990-07-01	159
1990-10-01	144
1991-01-01	320
1991-04-01	312
1991-07-01	348
1991-10-01	371
1992-01-01	132
1992-04-01	162
1992-07-01	220
1992-10-01	98
1993-01-01	105
1993-04-01	95
1993-07-01	0
1993-10-01	0
1994-01-01	26
1994-04-01	52
1994-07-01	147
1994-10-01	93
1995-01-01	145
1995-04-01	154
1995-07-01	130
1995-10-01	126
1996-01-01	125
1996-04-01	40
1996-07-01	10
1996-10-01	146
1997-01-01	120
1997-04-01	343
1997-07-01	577
1997-10-01	514
1998-01-01	362
1998-04-01	13
1998-07-01	22
1998-10-01	494
1999-01-01	421
1999-04-01	301
1999-07-01	303
1999-10-01	250
2000-01-01	0
2000-04-01	108
2000-07-01	0
2000-10-01	27
2001-01-01	80
2001-04-01	226
2001-07-01	211
2001-10-01	76
2002-01-01	162
2002-04-01	115
2002-07-01	139
2002-10-01	119
2003-01-01	29
2003-04-01	83
2003-07-01	121
2003-10-01	262
2004-01-01	1582
2004-04-01	1566
2004-07-01	1475
2004-10-01	2157
2005-01-01	2257
2005-04-01	1373
2005-07-01	2156
2005-10-01	2924
2006-01-01	2300
2006-04-01	3264
2006-07-01	3539
2006-10-01	5217
2007-01-01	5375
2007-04-01	5243
2007-07-01	2944
2007-10-01	3725
2008-01-01	3410
2008-04-01	3207
2008-07-01	2493
2008-10-01	863
2009-01-01	759
2009-04-01	424
2009-07-01	439
2009-10-01	465
2010-01-01	32
2010-04-01	34
2010-07-01	36
2010-10-01	2124
2011-01-01	2290
2011-04-01	2325
2011-07-01	2288
2011-10-01	138
2012-01-01	1235
2012-04-01	1794
2012-07-01	1871
2012-10-01	2038
2013-01-01	2666
2013-04-01	3446
2013-07-01	3568
2013-10-01	5706
2014-01-01	3017
2014-04-01	3841
2014-07-01	3852
2014-10-01	2991
2015-01-01	4412
2015-04-01	4021
2015-07-01	4115
2015-10-01	5043
2016-01-01	5002
2016-04-01	5306
2016-07-01	4977
2016-10-01	4607
2017-01-01	6046
2017-04-01	6915
2017-07-01	7109
2017-10-01	6737
2018-01-01	4124
2018-04-01	2601