Quarter	Millions of US Dollars
1978-01-01	15
1978-04-01	15
1978-07-01	15
1978-10-01	15
1979-01-01	15
1979-04-01	15
1979-07-01	15
1979-10-01	15
1980-01-01	15
1980-04-01	15
1980-07-01	15
1980-10-01	15
1981-01-01	15
1981-04-01	59
1981-07-01	58
1981-10-01	61
1982-01-01	55
1982-04-01	54
1982-07-01	52
1982-10-01	58
1983-01-01	57
1983-04-01	57
1983-07-01	57
1983-10-01	58
1984-01-01	60
1984-04-01	57
1984-07-01	56
1984-10-01	55
1985-01-01	55
1985-04-01	55
1985-07-01	61
1985-10-01	65
1986-01-01	71
1986-04-01	76
1986-07-01	80
1986-10-01	78
1987-01-01	83
1987-04-01	83
1987-07-01	83
1987-10-01	97
1988-01-01	96
1988-04-01	90
1988-07-01	89
1988-10-01	95
1989-01-01	90
1989-04-01	85
1989-07-01	87
1989-10-01	85
1990-01-01	63
1990-04-01	66
1990-07-01	72
1990-10-01	95
1991-01-01	92
1991-04-01	108
1991-07-01	111
1991-10-01	266
1992-01-01	406
1992-04-01	541
1992-07-01	872
1992-10-01	876
1993-01-01	957
1993-04-01	1060
1993-07-01	1916
1993-10-01	3571
1994-01-01	4268
1994-04-01	4397
1994-07-01	4482
1994-10-01	5213
1995-01-01	5041
1995-04-01	4994
1995-07-01	5091
1995-10-01	5679
1996-01-01	5653
1996-04-01	6260
1996-07-01	6576
1996-10-01	6401
1997-01-01	7773
1997-04-01	8572
1997-07-01	10268
1997-10-01	9988
1998-01-01	10687
1998-04-01	12950
1998-07-01	12969
1998-10-01	12925
1999-01-01	12880
1999-04-01	13591
1999-07-01	13951
1999-10-01	13310
2000-01-01	13368
2000-04-01	13857
2000-07-01	14135
2000-10-01	12979
2001-01-01	12905
2001-04-01	12573
2001-07-01	12518
2001-10-01	11910
2002-01-01	11262
2002-04-01	11106
2002-07-01	10161
2002-10-01	10002
2003-01-01	9335
2003-04-01	8444
2003-07-01	7603
2003-10-01	7779
2004-01-01	6747
2004-04-01	6468
2004-07-01	5836
2004-10-01	5857
2005-01-01	5893
2005-04-01	5347
2005-07-01	5309
2005-10-01	5625
2006-01-01	5704
2006-04-01	5529
2006-07-01	5852
2006-10-01	6094
2007-01-01	5593
2007-04-01	6525
2007-07-01	6239
2007-10-01	6945
2008-01-01	6641
2008-04-01	5366
2008-07-01	5031
2008-10-01	5031
2009-01-01	4586
2009-04-01	4138
2009-07-01	3938
2009-10-01	3859
2010-01-01	3859
2010-04-01	4335
2010-07-01	4610
2010-10-01	5023
2011-01-01	5405
2011-04-01	5545
2011-07-01	5628
2011-10-01	5580
2012-01-01	5170
2012-04-01	5183
2012-07-01	5008
2012-10-01	4996
2013-01-01	4896
2013-04-01	4889
2013-07-01	4889
2013-10-01	5339
2014-01-01	5241
2014-04-01	6241
2014-07-01	5994
2014-10-01	5718
2015-01-01	6218
2015-04-01	7718
2015-07-01	7776
2015-10-01	7876
2016-01-01	9236
2016-04-01	9854
2016-07-01	12109
2016-10-01	12256
2017-01-01	14012
2017-04-01	14164
2017-07-01	14944
2017-10-01	17005
2018-01-01	18229
2018-04-01	18503