Quarter	Millions of US Dollars
1966-01-01	20
1966-04-01	20
1966-07-01	20
1966-10-01	20
1967-01-01	20
1967-04-01	20
1967-07-01	20
1967-10-01	35
1968-01-01	35
1968-04-01	35
1968-07-01	35
1968-10-01	35
1969-01-01	35
1969-04-01	35
1969-07-01	35
1969-10-01	35
1970-01-01	35
1970-04-01	35
1970-07-01	35
1970-10-01	35
1971-01-01	50
1971-04-01	50
1971-07-01	65
1971-10-01	65
1972-01-01	186
1972-04-01	217
1972-07-01	240
1972-10-01	307
1973-01-01	413
1973-04-01	488
1973-07-01	485
1973-10-01	503
1974-01-01	546
1974-04-01	594
1974-07-01	590
1974-10-01	704
1975-01-01	1015
1975-04-01	1363
1975-07-01	1343
1975-10-01	1672
1976-01-01	1983
1976-04-01	2154
1976-07-01	2475
1976-10-01	2888
1977-01-01	3183
1977-04-01	3637
1977-07-01	4049
1977-10-01	4800
1978-01-01	5050
1978-04-01	5484
1978-07-01	5972
1978-10-01	6085
1979-01-01	6193
1979-04-01	7037
1979-07-01	7343
1979-10-01	7654
1980-01-01	7715
1980-04-01	9193
1980-07-01	9784
1980-10-01	10105
1981-01-01	10324
1981-04-01	10099
1981-07-01	10357
1981-10-01	11100
1982-01-01	11903
1982-04-01	11763
1982-07-01	11908
1982-10-01	12885
1983-01-01	14541
1983-04-01	14002
1983-07-01	13976
1983-10-01	14990
1984-01-01	15903
1984-04-01	17470
1984-07-01	18112
1984-10-01	19814
1985-01-01	18679
1985-04-01	21892
1985-07-01	23184
1985-10-01	22704
1986-01-01	24356
1986-04-01	25997
1986-07-01	28175
1986-10-01	28722
1987-01-01	34447
1987-04-01	35250
1987-07-01	35596
1987-10-01	38117
1988-01-01	39536
1988-04-01	38777
1988-07-01	38903
1988-10-01	40814
1989-01-01	42796
1989-04-01	42537
1989-07-01	44806
1989-10-01	47458
1990-01-01	49318
1990-04-01	51205
1990-07-01	55927
1990-10-01	55698
1991-01-01	52503
1991-04-01	52472
1991-07-01	55170
1991-10-01	55586
1992-01-01	52320
1992-04-01	56930
1992-07-01	61631
1992-10-01	60933
1993-01-01	64540
1993-04-01	73238
1993-07-01	80153
1993-10-01	81829
1994-01-01	88663
1994-04-01	97187
1994-07-01	102412
1994-10-01	103375
1995-01-01	107792
1995-04-01	109576
1995-07-01	109823
1995-10-01	108016
1996-01-01	108936
1996-04-01	112453
1996-07-01	111176
1996-10-01	110433
1997-01-01	106301
1997-04-01	107927
1997-07-01	106889
1997-10-01	102007
1998-01-01	96491
1998-04-01	100260
1998-07-01	100826
1998-10-01	99719
1999-01-01	91905
1999-04-01	94591
1999-07-01	102124
1999-10-01	100354
2000-01-01	102421
2000-04-01	101986
2000-07-01	96665
2000-10-01	100823
2001-01-01	96521
2001-04-01	97833
2001-07-01	99152
2001-10-01	98661
2002-01-01	98004
2002-04-01	111025
2002-07-01	111311
2002-10-01	114865
2003-01-01	119319
2003-04-01	123065
2003-07-01	127045
2003-10-01	139484
2004-01-01	145190
2004-04-01	144271
2004-07-01	148630
2004-10-01	163918
2005-01-01	162045
2005-04-01	169310
2005-07-01	173047
2005-10-01	169024
2006-01-01	183523
2006-04-01	189978
2006-07-01	188512
2006-10-01	202621
2007-01-01	218496
2007-04-01	243449
2007-07-01	250515
2007-10-01	266121
2008-01-01	279360
2008-04-01	303373
2008-07-01	299916
2008-10-01	278397
2009-01-01	293834
2009-04-01	340489
2009-07-01	373665
2009-10-01	377199
2010-01-01	389484
2010-04-01	357237
2010-07-01	386109
2010-10-01	392137
2011-01-01	414626
2011-04-01	441173
2011-07-01	435944
2011-10-01	424448
2012-01-01	451209
2012-04-01	450100
2012-07-01	470132
2012-10-01	484486
2013-01-01	490606
2013-04-01	494848
2013-07-01	523503
2013-10-01	516408
2014-01-01	517723
2014-04-01	515099
2014-07-01	494641
2014-10-01	490984
2015-01-01	459877
2015-04-01	471591
2015-07-01	476599
2015-10-01	480036
2016-01-01	490142
2016-04-01	474787
2016-07-01	474719
2016-10-01	461682
2017-01-01	482399
2017-04-01	503278
2017-07-01	511869
2017-10-01	509666
2018-01-01	523824
2018-04-01	509910