Quarter	Millions of US Dollars
1971-10-01	31
1972-01-01	113
1972-04-01	153
1972-07-01	204
1972-10-01	349
1973-01-01	456
1973-04-01	499
1973-07-01	575
1973-10-01	669
1974-01-01	683
1974-04-01	678
1974-07-01	671
1974-10-01	757
1975-01-01	893
1975-04-01	1039
1975-07-01	1064
1975-10-01	1128
1976-01-01	1198
1976-04-01	1390
1976-07-01	1542
1976-10-01	1822
1977-01-01	2141
1977-04-01	2779
1977-07-01	3681
1977-10-01	4963
1978-01-01	6299
1978-04-01	7024
1978-07-01	7853
1978-10-01	8548
1979-01-01	8878
1979-04-01	9138
1979-07-01	9852
1979-10-01	10016
1980-01-01	9368
1980-04-01	10612
1980-07-01	10841
1980-10-01	10826
1981-01-01	10608
1981-04-01	10759
1981-07-01	11288
1981-10-01	12480
1982-01-01	12553
1982-04-01	12152
1982-07-01	11940
1982-10-01	12348
1983-01-01	11756
1983-04-01	11470
1983-07-01	11365
1983-10-01	11046
1984-01-01	11097
1984-04-01	10595
1984-07-01	9953
1984-10-01	9670
1985-01-01	9699
1985-04-01	9695
1985-07-01	10276
1985-10-01	9623
1986-01-01	9950
1986-04-01	9967
1986-07-01	10131
1986-10-01	9536
1987-01-01	9949
1987-04-01	9406
1987-07-01	9216
1987-10-01	9599
1988-01-01	9291
1988-04-01	8041
1988-07-01	7015
1988-10-01	7053
1989-01-01	6623
1989-04-01	6313
1989-07-01	7283
1989-10-01	6797
1990-01-01	42063
1990-04-01	43125
1990-07-01	44208
1990-10-01	61697
1991-01-01	61075
1991-04-01	62057
1991-07-01	63793
1991-10-01	67580
1992-01-01	68090
1992-04-01	70936
1992-07-01	73507
1992-10-01	75602
1993-01-01	77302
1993-04-01	100420
1993-07-01	108631
1993-10-01	124282
1994-01-01	131997
1994-04-01	177061
1994-07-01	180387
1994-10-01	182664
1995-01-01	183864
1995-04-01	187668
1995-07-01	193366
1995-10-01	198060
1996-01-01	206442
1996-04-01	217459
1996-07-01	224452
1996-10-01	231389
1997-01-01	243264
1997-04-01	256712
1997-07-01	268107
1997-10-01	265380
1998-01-01	273702
1998-04-01	287436
1998-07-01	290824
1998-10-01	269103
1999-01-01	266806
1999-04-01	279077
1999-07-01	286740
1999-10-01	293152
2000-01-01	306401
2000-04-01	303662
2000-07-01	315506
2000-10-01	314396
2001-01-01	322050
2001-04-01	315811
2001-07-01	320133
2001-10-01	313353
2002-01-01	316158
2002-04-01	320750
2002-07-01	319870
2002-10-01	325523
2003-01-01	324158
2003-04-01	327949
2003-07-01	330221
2003-10-01	339765
2004-01-01	343267
2004-04-01	338936
2004-07-01	341401
2004-10-01	352809
2005-01-01	355865
2005-04-01	321253
2005-07-01	324152
2005-10-01	330644
2006-01-01	337301
2006-04-01	323760
2006-07-01	328093
2006-10-01	343041
2007-01-01	352653
2007-04-01	370719
2007-07-01	366781
2007-10-01	377355
2008-01-01	378144
2008-04-01	383369
2008-07-01	371391
2008-10-01	355714
2009-01-01	351899
2009-04-01	353397
2009-07-01	374310
2009-10-01	405947
2010-01-01	414852
2010-04-01	425898
2010-07-01	455963
2010-10-01	467139
2011-01-01	491839
2011-04-01	512919
2011-07-01	516275
2011-10-01	537396
2012-01-01	576267
2012-04-01	586452
2012-07-01	612068
2012-10-01	638342
2013-01-01	655478
2013-04-01	681871
2013-07-01	705453
2013-10-01	729242
2014-01-01	752641
2014-04-01	788236
2014-07-01	801042
2014-10-01	798895
2015-01-01	793096
2015-04-01	817996
2015-07-01	814299
2015-10-01	808721
2016-01-01	832140
2016-04-01	858458
2016-07-01	874784
2016-10-01	885383
2017-01-01	911673
2017-04-01	936359
2017-07-01	969577
2017-10-01	983882
2018-01-01	1009233
2018-04-01	993378