Quarter	Millions of US Dollars
1966-01-01	0
1966-04-01	0
1966-07-01	0
1966-10-01	0
1967-01-01	0
1967-04-01	0
1967-07-01	0
1967-10-01	0
1968-01-01	0
1968-04-01	0
1968-07-01	0
1968-10-01	0
1969-01-01	0
1969-04-01	0
1969-07-01	0
1969-10-01	0
1970-01-01	0
1970-04-01	0
1970-07-01	0
1970-10-01	0
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	34
1977-10-01	50
1978-01-01	54
1978-04-01	54
1978-07-01	13
1978-10-01	96
1979-01-01	96
1979-04-01	267
1979-07-01	275
1979-10-01	192
1980-01-01	199
1980-04-01	75
1980-07-01	149
1980-10-01	158
1981-01-01	206
1981-04-01	221
1981-07-01	228
1981-10-01	249
1982-01-01	312
1982-04-01	321
1982-07-01	318
1982-10-01	504
1983-01-01	943
1983-04-01	1296
1983-07-01	1736
1983-10-01	2104
1984-01-01	2003
1984-04-01	2587
1984-07-01	3366
1984-10-01	5898
1985-01-01	7165
1985-04-01	9066
1985-07-01	10611
1985-10-01	10577
1986-01-01	11150
1986-04-01	10810
1986-07-01	9994
1986-10-01	9210
1987-01-01	8873
1987-04-01	8290
1987-07-01	7532
1987-10-01	7594
1988-01-01	7094
1988-04-01	6023
1988-07-01	6943
1988-10-01	7651
1989-01-01	8628
1989-04-01	10324
1989-07-01	9512
1989-10-01	9750
1990-01-01	10344
1990-04-01	9883
1990-07-01	11626
1990-10-01	13214
1991-01-01	17651
1991-04-01	19410
1991-07-01	19960
1991-10-01	19586
1992-01-01	16907
1992-04-01	18604
1992-07-01	22314
1992-10-01	23599
1993-01-01	22251
1993-04-01	20057
1993-07-01	23397
1993-10-01	21763
1994-01-01	22354
1994-04-01	22818
1994-07-01	26439
1994-10-01	29421
1995-01-01	35119
1995-04-01	38117
1995-07-01	38425
1995-10-01	41994
1996-01-01	44253
1996-04-01	45552
1996-07-01	39527
1996-10-01	47098
1997-01-01	48785
1997-04-01	48301
1997-07-01	51101
1997-10-01	60544
1998-01-01	59780
1998-04-01	63041
1998-07-01	64405
1998-10-01	67297
1999-01-01	70316
1999-04-01	75761
1999-07-01	89468
1999-10-01	85435
2000-01-01	94153
2000-04-01	95542
2000-07-01	89998
2000-10-01	101552
2001-01-01	104308
2001-04-01	97122
2001-07-01	104643
2001-10-01	102550
2002-01-01	101905
2002-04-01	112196
2002-07-01	118340
2002-10-01	131199
2003-01-01	138346
2003-04-01	141225
2003-07-01	139269
2003-10-01	142397
2004-01-01	136165
2004-04-01	138597
2004-07-01	138935
2004-10-01	147370
2005-01-01	157674
2005-04-01	145677
2005-07-01	145079
2005-10-01	140814
2006-01-01	155733
2006-04-01	160048
2006-07-01	162594
2006-10-01	163259
2007-01-01	176432
2007-04-01	189531
2007-07-01	177697
2007-10-01	183511
2008-01-01	173277
2008-04-01	168934
2008-07-01	157610
2008-10-01	153990
2009-01-01	136030
2009-04-01	138908
2009-07-01	135933
2009-10-01	126774
2010-01-01	135897
2010-04-01	134649
2010-07-01	146647
2010-10-01	143284
2011-01-01	140442
2011-04-01	148895
2011-07-01	144730
2011-10-01	147028
2012-01-01	150570
2012-04-01	155090
2012-07-01	171923
2012-10-01	175060
2013-01-01	181937
2013-04-01	200259
2013-07-01	204726
2013-10-01	211247
2014-01-01	217862
2014-04-01	219924
2014-07-01	226424
2014-10-01	225257
2015-01-01	218369
2015-04-01	223924
2015-07-01	219467
2015-10-01	232271
2016-01-01	265260
2016-04-01	282441
2016-07-01	291620
2016-10-01	295830
2017-01-01	286173
2017-04-01	293698
2017-07-01	287292
2017-10-01	295929
2018-01-01	301890
2018-04-01	307687