Quarter	Millions of US Dollars
1977-04-01	50
1977-07-01	50
1977-10-01	50
1978-01-01	50
1978-04-01	50
1978-07-01	50
1978-10-01	50
1979-01-01	50
1979-04-01	50
1979-07-01	50
1979-10-01	50
1980-01-01	50
1980-04-01	80
1980-07-01	80
1980-10-01	80
1981-01-01	80
1981-04-01	80
1981-07-01	80
1981-10-01	80
1982-01-01	80
1982-04-01	30
1982-07-01	49
1982-10-01	76
1983-01-01	96
1983-04-01	95
1983-07-01	96
1983-10-01	126
1984-01-01	250
1984-04-01	368
1984-07-01	403
1984-10-01	438
1985-01-01	479
1985-04-01	539
1985-07-01	731
1985-10-01	824
1986-01-01	965
1986-04-01	1198
1986-07-01	1389
1986-10-01	1416
1987-01-01	1940
1987-04-01	2169
1987-07-01	2574
1987-10-01	2981
1988-01-01	3437
1988-04-01	3848
1988-07-01	3787
1988-10-01	4620
1989-01-01	4392
1989-04-01	4224
1989-07-01	4316
1989-10-01	4290
1990-01-01	4100
1990-04-01	4190
1990-07-01	4317
1990-10-01	3582
1991-01-01	2583
1991-04-01	2395
1991-07-01	2470
1991-10-01	2864
1992-01-01	2660
1992-04-01	2752
1992-07-01	2672
1992-10-01	2364
1993-01-01	2993
1993-04-01	2766
1993-07-01	3725
1993-10-01	4519
1994-01-01	5439
1994-04-01	5499
1994-07-01	7163
1994-10-01	7563
1995-01-01	9182
1995-04-01	10503
1995-07-01	9869
1995-10-01	10959
1996-01-01	11081
1996-04-01	12160
1996-07-01	11838
1996-10-01	11569
1997-01-01	11514
1997-04-01	12270
1997-07-01	12572
1997-10-01	13040
1998-01-01	13498
1998-04-01	13810
1998-07-01	14593
1998-10-01	14911
1999-01-01	12698
1999-04-01	12480
1999-07-01	12621
1999-10-01	14563
2000-01-01	14306
2000-04-01	14221
2000-07-01	13727
2000-10-01	14796
2001-01-01	16117
2001-04-01	16522
2001-07-01	18455
2001-10-01	19383
2002-01-01	21227
2002-04-01	25320
2002-07-01	25645
2002-10-01	26945
2003-01-01	30830
2003-04-01	33170
2003-07-01	35503
2003-10-01	39183
2004-01-01	35910
2004-04-01	38817
2004-07-01	38184
2004-10-01	41504
2005-01-01	39602
2005-04-01	36688
2005-07-01	36053
2005-10-01	42644
2006-01-01	46718
2006-04-01	49749
2006-07-01	52355
2006-10-01	60487
2007-01-01	60482
2007-04-01	73947
2007-07-01	75733
2007-10-01	80583
2008-01-01	92435
2008-04-01	104602
2008-07-01	97140
2008-10-01	99214
2009-01-01	105010
2009-04-01	122627
2009-07-01	136278
2009-10-01	144213
2010-01-01	139979
2010-04-01	124452
2010-07-01	138519
2010-10-01	136188
2011-01-01	145075
2011-04-01	138133
2011-07-01	127690
2011-10-01	124190
2012-01-01	119916
2012-04-01	108114
2012-07-01	104325
2012-10-01	110814
2013-01-01	105060
2013-04-01	99954
2013-07-01	102310
2013-10-01	104291
2014-01-01	100711
2014-04-01	91021
2014-07-01	87241
2014-10-01	75584
2015-01-01	65968
2015-04-01	69108
2015-07-01	67870
2015-10-01	65526
2016-01-01	68319
2016-04-01	65344
2016-07-01	66759
2016-10-01	56230
2017-01-01	52840
2017-04-01	57823
2017-07-01	60520
2017-10-01	60256
2018-01-01	64677
2018-04-01	62553
