Quarter	Millions of US Dollars
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	20
1977-01-01	20
1977-04-01	20
1977-07-01	20
1977-10-01	0
1978-01-01	0
1978-04-01	0
1978-07-01	0
1978-10-01	0
1979-01-01	0
1979-04-01	0
1979-07-01	0
1979-10-01	0
1980-01-01	14
1980-04-01	59
1980-07-01	58
1980-10-01	124
1981-01-01	122
1981-04-01	199
1981-07-01	203
1981-10-01	185
1982-01-01	265
1982-04-01	142
1982-07-01	141
1982-10-01	182
1983-01-01	113
1983-04-01	244
1983-07-01	289
1983-10-01	338
1984-01-01	352
1984-04-01	179
1984-07-01	146
1984-10-01	351
1985-01-01	637
1985-04-01	636
1985-07-01	1093
1985-10-01	1968
1986-01-01	1999
1986-04-01	2484
1986-07-01	2145
1986-10-01	1114
1987-01-01	1038
1987-04-01	778
1987-07-01	891
1987-10-01	1017
1988-01-01	809
1988-04-01	454
1988-07-01	543
1988-10-01	622
1989-01-01	644
1989-04-01	610
1989-07-01	619
1989-10-01	595
1990-01-01	557
1990-04-01	584
1990-07-01	358
1990-10-01	390
1991-01-01	227
1991-04-01	567
1991-07-01	725
1991-10-01	756
1992-01-01	981
1992-04-01	976
1992-07-01	1140
1992-10-01	1175
1993-01-01	1171
1993-04-01	1431
1993-07-01	3492
1993-10-01	3267
1994-01-01	2683
1994-04-01	2045
1994-07-01	2559
1994-10-01	2247
1995-01-01	3333
1995-04-01	3087
1995-07-01	2751
1995-10-01	2566
1996-01-01	1578
1996-04-01	1691
1996-07-01	522
1996-10-01	1126
1997-01-01	1564
1997-04-01	1605
1997-07-01	1723
1997-10-01	2165
1998-01-01	3450
1998-04-01	3474
1998-07-01	5292
1998-10-01	4404
1999-01-01	3909
1999-04-01	4090
1999-07-01	3928
1999-10-01	5056
2000-01-01	2545
2000-04-01	3462
2000-07-01	2922
2000-10-01	3511
2001-01-01	4991
2001-04-01	5901
2001-07-01	6647
2001-10-01	6854
2002-01-01	7851
2002-04-01	7029
2002-07-01	6316
2002-10-01	5857
2003-01-01	3611
2003-04-01	5782
2003-07-01	10272
2003-10-01	12559
2004-01-01	14895
2004-04-01	13121
2004-07-01	12717
2004-10-01	16731
2005-01-01	15093
2005-04-01	20678
2005-07-01	20714
2005-10-01	27726
2006-01-01	28897
2006-04-01	24288
2006-07-01	32667
2006-10-01	33791
2007-01-01	41604
2007-04-01	55190
2007-07-01	61758
2007-10-01	68891
2008-01-01	84505
2008-04-01	100541
2008-07-01	106433
2008-10-01	98315
2009-01-01	117648
2009-04-01	142679
2009-07-01	143368
2009-10-01	133366
2010-01-01	122872
2010-04-01	101378
2010-07-01	108248
2010-10-01	104112
2011-01-01	104501
2011-04-01	104697
2011-07-01	116542
2011-10-01	111153
2012-01-01	124699
2012-04-01	116870
2012-07-01	118636
2012-10-01	116508
2013-01-01	127572
2013-04-01	112041
2013-07-01	106315
2013-10-01	122111
2014-01-01	113411
2014-04-01	116574
2014-07-01	107262
2014-10-01	99017
2015-01-01	104943
2015-04-01	109582
2015-07-01	103612
2015-10-01	105246
2016-01-01	108879
2016-04-01	102124
2016-07-01	119659
2016-10-01	97272
2017-01-01	82968
2017-04-01	87509
2017-07-01	76525
2017-10-01	73026
2018-01-01	63465
2018-04-01	52428