Quarter	Millions of US Dollars
1966-01-01	0
1966-04-01	0
1966-07-01	0
1966-10-01	0
1967-01-01	0
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	4
1977-01-01	4
1977-04-01	4
1977-07-01	4
1977-10-01	30
1978-01-01	32
1978-04-01	32
1978-07-01	39
1978-10-01	48
1979-01-01	80
1979-04-01	133
1979-07-01	199
1979-10-01	341
1980-01-01	370
1980-04-01	405
1980-07-01	344
1980-10-01	289
1981-01-01	257
1981-04-01	456
1981-07-01	537
1981-10-01	485
1982-01-01	651
1982-04-01	992
1982-07-01	1179
1982-10-01	1258
1983-01-01	1251
1983-04-01	990
1983-07-01	935
1983-10-01	1318
1984-01-01	3396
1984-04-01	3377
1984-07-01	3449
1984-10-01	4998
1985-01-01	3968
1985-04-01	4346
1985-07-01	4636
1985-10-01	4230
1986-01-01	3720
1986-04-01	3807
1986-07-01	4263
1986-10-01	3450
1987-01-01	3693
1987-04-01	5655
1987-07-01	5360
1987-10-01	5778
1988-01-01	5701
1988-04-01	3825
1988-07-01	3439
1988-10-01	3320
1989-01-01	3154
1989-04-01	4526
1989-07-01	5223
1989-10-01	6112
1990-01-01	6966
1990-04-01	5953
1990-07-01	6481
1990-10-01	8483
1991-01-01	9109
1991-04-01	8959
1991-07-01	9356
1991-10-01	7802
1992-01-01	6640
1992-04-01	8214
1992-07-01	10011
1992-10-01	10140
1993-01-01	11092
1993-04-01	10543
1993-07-01	20850
1993-10-01	19721
1994-01-01	20685
1994-04-01	21928
1994-07-01	21536
1994-10-01	26045
1995-01-01	26076
1995-04-01	26947
1995-07-01	28601
1995-10-01	27784
1996-01-01	27703
1996-04-01	28966
1996-07-01	24896
1996-10-01	28842
1997-01-01	27119
1997-04-01	29166
1997-07-01	30282
1997-10-01	28982
1998-01-01	29364
1998-04-01	30236
1998-07-01	30061
1998-10-01	27779
1999-01-01	25895
1999-04-01	25935
1999-07-01	32725
1999-10-01	31235
2000-01-01	31826
2000-04-01	31460
2000-07-01	28907
2000-10-01	30856
2001-01-01	28345
2001-04-01	27314
2001-07-01	28379
2001-10-01	30833
2002-01-01	31313
2002-04-01	34402
2002-07-01	35467
2002-10-01	31424
2003-01-01	31316
2003-04-01	29262
2003-07-01	28414
2003-10-01	35666
2004-01-01	39459
2004-04-01	37418
2004-07-01	40953
2004-10-01	50622
2005-01-01	49002
2005-04-01	58897
2005-07-01	61257
2005-10-01	58177
2006-01-01	63335
2006-04-01	64218
2006-07-01	61764
2006-10-01	60913
2007-01-01	69342
2007-04-01	74120
2007-07-01	77125
2007-10-01	94214
2008-01-01	100850
2008-04-01	108293
2008-07-01	112002
2008-10-01	89996
2009-01-01	90584
2009-04-01	114563
2009-07-01	121376
2009-10-01	117628
2010-01-01	128188
2010-04-01	102501
2010-07-01	112293
2010-10-01	119140
2011-01-01	109579
2011-04-01	108888
2011-07-01	116666
2011-10-01	114075
2012-01-01	114134
2012-04-01	122084
2012-07-01	120143
2012-10-01	123674
2013-01-01	124139
2013-04-01	134872
2013-07-01	143368
2013-10-01	136689
2014-01-01	128031
2014-04-01	120931
2014-07-01	117476
2014-10-01	119960
2015-01-01	106824
2015-04-01	107926
2015-07-01	116016
2015-10-01	114177
2016-01-01	113051
2016-04-01	114258
2016-07-01	116253
2016-10-01	117083
2017-01-01	120469
2017-04-01	120317
2017-07-01	115613
2017-10-01	117534
2018-01-01	114299
2018-04-01	112123