Quarter	Millions of US Dollars
1972-01-01	50
1972-04-01	86
1972-07-01	186
1972-10-01	204
1973-01-01	221
1973-04-01	233
1973-07-01	235
1973-10-01	224
1974-01-01	230
1974-04-01	245
1974-07-01	341
1974-10-01	384
1975-01-01	600
1975-04-01	956
1975-07-01	912
1975-10-01	957
1976-01-01	1061
1976-04-01	1297
1976-07-01	1723
1976-10-01	2011
1977-01-01	2070
1977-04-01	2171
1977-07-01	2668
1977-10-01	3132
1978-01-01	3791
1978-04-01	4047
1978-07-01	4582
1978-10-01	4864
1979-01-01	5030
1979-04-01	5145
1979-07-01	5265
1979-10-01	5366
1980-01-01	5311
1980-04-01	5524
1980-07-01	5612
1980-10-01	5524
1981-01-01	5449
1981-04-01	5301
1981-07-01	5411
1981-10-01	5986
1982-01-01	5801
1982-04-01	5775
1982-07-01	6498
1982-10-01	7074
1983-01-01	7143
1983-04-01	7050
1983-07-01	7474
1983-10-01	8073
1984-01-01	8830
1984-04-01	9086
1984-07-01	9153
1984-10-01	9782
1985-01-01	10577
1985-04-01	11780
1985-07-01	14477
1985-10-01	16184
1986-01-01	18931
1986-04-01	21420
1986-07-01	23228
1986-10-01	25479
1987-01-01	35055
1987-04-01	37295
1987-07-01	41124
1987-10-01	44755
1988-01-01	43756
1988-04-01	46724
1988-07-01	49470
1988-10-01	54464
1989-01-01	57332
1989-04-01	55348
1989-07-01	60208
1989-10-01	62156
1990-01-01	64184
1990-04-01	65392
1990-07-01	69781
1990-10-01	68719
1991-01-01	70479
1991-04-01	67617
1991-07-01	70963
1991-10-01	71996
1992-01-01	70016
1992-04-01	70619
1992-07-01	72011
1992-10-01	67640
1993-01-01	66825
1993-04-01	67738
1993-07-01	70234
1993-10-01	70626
1994-01-01	75104
1994-04-01	75169
1994-07-01	78186
1994-10-01	80768
1995-01-01	85143
1995-04-01	85409
1995-07-01	88868
1995-10-01	89083
1996-01-01	92811
1996-04-01	95613
1996-07-01	102204
1996-10-01	104099
1997-01-01	106592
1997-04-01	108943
1997-07-01	109040
1997-10-01	98867
1998-01-01	102447
1998-04-01	98981
1998-07-01	102848
1998-10-01	103844
1999-01-01	109906
1999-04-01	106410
1999-07-01	116285
1999-10-01	118278
2000-01-01	120470
2000-04-01	122325
2000-07-01	122523
2000-10-01	125042
2001-01-01	123024
2001-04-01	128941
2001-07-01	134633
2001-10-01	134665
2002-01-01	138532
2002-04-01	150904
2002-07-01	153950
2002-10-01	160631
2003-01-01	169536
2003-04-01	183576
2003-07-01	194902
2003-10-01	220085
2004-01-01	239196
2004-04-01	244349
2004-07-01	268802
2004-10-01	288922
2005-01-01	292154
2005-04-01	299851
2005-07-01	300115
2005-10-01	306500
2006-01-01	329507
2006-04-01	355831
2006-07-01	372063
2006-10-01	402174
2007-01-01	419318
2007-04-01	451264
2007-07-01	462885
2007-10-01	458502
2008-01-01	514824
2008-04-01	522534
2008-07-01	471891
2008-10-01	426740
2009-01-01	407195
2009-04-01	449793
2009-07-01	485247
2009-10-01	514004
2010-01-01	519139
2010-04-01	501245
2010-07-01	542903
2010-10-01	550136
2011-01-01	556694
2011-04-01	578614
2011-07-01	553643
2011-10-01	545667
2012-01-01	567707
2012-04-01	558931
2012-07-01	589394
2012-10-01	591899
2013-01-01	593502
2013-04-01	588126
2013-07-01	609472
2013-10-01	623633
2014-01-01	627946
2014-04-01	642433
2014-07-01	614526
2014-10-01	601958
2015-01-01	583368
2015-04-01	598803
2015-07-01	575185
2015-10-01	582877
2016-01-01	604203
2016-04-01	609260
2016-07-01	617699
2016-10-01	590408
2017-01-01	593923
2017-04-01	601662
2017-07-01	610290
2017-10-01	608964
2018-01-01	633321
2018-04-01	624133