Quarter	Millions of US Dollars
1967-04-01	20
1967-07-01	20
1967-10-01	20
1968-01-01	20
1968-04-01	20
1968-07-01	20
1968-10-01	20
1969-01-01	20
1969-04-01	20
1969-07-01	20
1969-10-01	20
1970-01-01	20
1970-04-01	20
1970-07-01	20
1970-10-01	20
1971-01-01	48
1971-04-01	49
1971-07-01	50
1971-10-01	96
1972-01-01	130
1972-04-01	130
1972-07-01	160
1972-10-01	226
1973-01-01	317
1973-04-01	363
1973-07-01	365
1973-10-01	342
1974-01-01	355
1974-04-01	352
1974-07-01	371
1974-10-01	390
1975-01-01	417
1975-04-01	434
1975-07-01	433
1975-10-01	436
1976-01-01	452
1976-04-01	517
1976-07-01	585
1976-10-01	737
1977-01-01	892
1977-04-01	1091
1977-07-01	1127
1977-10-01	1294
1978-01-01	1301
1978-04-01	1525
1978-07-01	1667
1978-10-01	1691
1979-01-01	1882
1979-04-01	2031
1979-07-01	2179
1979-10-01	2194
1980-01-01	2101
1980-04-01	2482
1980-07-01	2531
1980-10-01	2487
1981-01-01	2352
1981-04-01	2335
1981-07-01	2346
1981-10-01	2519
1982-01-01	2629
1982-04-01	2877
1982-07-01	2818
1982-10-01	2999
1983-01-01	3163
1983-04-01	3239
1983-07-01	3459
1983-10-01	3849
1984-01-01	4409
1984-04-01	4094
1984-07-01	4004
1984-10-01	4592
1985-01-01	5166
1985-04-01	5665
1985-07-01	6097
1985-10-01	6397
1986-01-01	6489
1986-04-01	6768
1986-07-01	7723
1986-10-01	7367
1987-01-01	8022
1987-04-01	7613
1987-07-01	8354
1987-10-01	9343
1988-01-01	9485
1988-04-01	9362
1988-07-01	10234
1988-10-01	11156
1989-01-01	11652
1989-04-01	10989
1989-07-01	11976
1989-10-01	12112
1990-01-01	13003
1990-04-01	14562
1990-07-01	17679
1990-10-01	18724
1991-01-01	17866
1991-04-01	18352
1991-07-01	19609
1991-10-01	22050
1992-01-01	22488
1992-04-01	26427
1992-07-01	28923
1992-10-01	27501
1993-01-01	29206
1993-04-01	33632
1993-07-01	43747
1993-10-01	45622
1994-01-01	49166
1994-04-01	52260
1994-07-01	55976
1994-10-01	57477
1995-01-01	68087
1995-04-01	69569
1995-07-01	70555
1995-10-01	72536
1996-01-01	77203
1996-04-01	79589
1996-07-01	84305
1996-10-01	91352
1997-01-01	90052
1997-04-01	92409
1997-07-01	96807
1997-10-01	98398
1998-01-01	105661
1998-04-01	113684
1998-07-01	124467
1998-10-01	128879
1999-01-01	133432
1999-04-01	146350
1999-07-01	156669
1999-10-01	159335
2000-01-01	163229
2000-04-01	171756
2000-07-01	177213
2000-10-01	186439
2001-01-01	190099
2001-04-01	189150
2001-07-01	200768
2001-10-01	207774
2002-01-01	211751
2002-04-01	244450
2002-07-01	240507
2002-10-01	257162
2003-01-01	281299
2003-04-01	308722
2003-07-01	322336
2003-10-01	374377
2004-01-01	365393
2004-04-01	368554
2004-07-01	369801
2004-10-01	416989
2005-01-01	412439
2005-04-01	421292
2005-07-01	430077
2005-10-01	476039
2006-01-01	554973
2006-04-01	633488
2006-07-01	655455
2006-10-01	713675
2007-01-01	800236
2007-04-01	864491
2007-07-01	936538
2007-10-01	987411
2008-01-01	1065145
2008-04-01	1137186
2008-07-01	1081271
2008-10-01	1067590
2009-01-01	1060442
2009-04-01	1145453
2009-07-01	1202328
2009-10-01	1195431
2010-01-01	1135313
2010-04-01	1034264
2010-07-01	1165661
2010-10-01	1129028
2011-01-01	1217114
2011-04-01	1248236
2011-07-01	1172706
2011-10-01	1124293
2012-01-01	1232981
2012-04-01	1141167
2012-07-01	1156631
2012-10-01	1184130
2013-01-01	1145413
2013-04-01	1146798
2013-07-01	1148855
2013-10-01	1183555
2014-01-01	1167148
2014-04-01	1166448
2014-07-01	1079280
2014-10-01	1024589
2015-01-01	939906
2015-04-01	954804
2015-07-01	944369
2015-10-01	918477
2016-01-01	918876
2016-04-01	900766
2016-07-01	903374
2016-10-01	840033
2017-01-01	823481
2017-04-01	873297
2017-07-01	890827
2017-10-01	900715
2018-01-01	915959
2018-04-01	862652