Quarter	Millions of US Dollars
1984-07-01	50
1984-10-01	50
1985-01-01	50
1985-04-01	50
1985-07-01	50
1985-10-01	50
1986-01-01	50
1986-04-01	150
1986-07-01	150
1986-10-01	150
1987-01-01	100
1987-04-01	100
1987-07-01	100
1987-10-01	100
1988-01-01	173
1988-04-01	166
1988-07-01	429
1988-10-01	449
1989-01-01	900
1989-04-01	888
1989-07-01	1394
1989-10-01	1529
1990-01-01	1790
1990-04-01	1796
1990-07-01	1911
1990-10-01	1990
1991-01-01	1751
1991-04-01	1662
1991-07-01	1926
1991-10-01	2085
1992-01-01	1943
1992-04-01	2073
1992-07-01	2245
1992-10-01	1988
1993-01-01	1982
1993-04-01	1813
1993-07-01	1837
1993-10-01	1727
1994-01-01	1693
1994-04-01	1772
1994-07-01	1776
1994-10-01	1773
1995-01-01	1626
1995-04-01	1622
1995-07-01	1131
1995-10-01	1157
1996-01-01	1195
1996-04-01	1205
1996-07-01	228
1996-10-01	1327
1997-01-01	2697
1997-04-01	5784
1997-07-01	6944
1997-10-01	8490
1998-01-01	9228
1998-04-01	14128
1998-07-01	20691
1998-10-01	20465
1999-01-01	20136
1999-04-01	19832
1999-07-01	19710
1999-10-01	19278
2000-01-01	19048
2000-04-01	18768
2000-07-01	38404
2000-10-01	38546
2001-01-01	38272
2001-04-01	37833
2001-07-01	37970
2001-10-01	38141
2002-01-01	38776
2002-04-01	39490
2002-07-01	39454
2002-10-01	41513
2003-01-01	44152
2003-04-01	44110
2003-07-01	45765
2003-10-01	48458
2004-01-01	48868
2004-04-01	51022
2004-07-01	54256
2004-10-01	56849
2005-01-01	58711
2005-04-01	63811
2005-07-01	64688
2005-10-01	69549
2006-01-01	72422
2006-04-01	75237
2006-07-01	79666
2006-10-01	94756
2007-01-01	104476
2007-04-01	118265
2007-07-01	120582
2007-10-01	132385
2008-01-01	134412
2008-04-01	144772
2008-07-01	144032
2008-10-01	139480
2009-01-01	134156
2009-04-01	138616
2009-07-01	140323
2009-10-01	136883
2010-01-01	136592
2010-04-01	139698
2010-07-01	149795
2010-10-01	163293
2011-01-01	169675
2011-04-01	176771
2011-07-01	171648
2011-10-01	170716
2012-01-01	176803
2012-04-01	194423
2012-07-01	226309
2012-10-01	241636
2013-01-01	250824
2013-04-01	261078
2013-07-01	268002
2013-10-01	275738
2014-01-01	262457
2014-04-01	259696
2014-07-01	251023
2014-10-01	245970
2015-01-01	237473
2015-04-01	233865
2015-07-01	227040
2015-10-01	223443
2016-01-01	220703
2016-04-01	220165
2016-07-01	217752
2016-10-01	222500
2017-01-01	214830
2017-04-01	214315
2017-07-01	220837
2017-10-01	213415
2018-01-01	207509
2018-04-01	194523