Quarter	Millions of US Dollars
1973-01-01	10
1976-07-01	100
1977-04-01	30
1978-07-01	30
1980-04-01	-45
1980-07-01	53
1982-10-01	100
1983-01-01	143
1983-04-01	150
1983-07-01	-9
1983-10-01	20
1984-07-01	40
1984-10-01	15
1985-10-01	-87
1986-04-01	52
1986-07-01	28
1986-10-01	154
1987-01-01	93
1987-04-01	297
1987-07-01	32
1988-01-01	-1
1988-07-01	81
1988-10-01	40
1989-01-01	117
1989-07-01	-10
1989-10-01	-115
1990-01-01	-150
1990-04-01	-150
1990-07-01	-32
1990-10-01	126
1991-01-01	-130
1991-10-01	-106
1992-01-01	-93
1992-04-01	-327
1992-07-01	-53
1993-04-01	-25
1993-07-01	237
1993-10-01	648
1994-01-01	169
1994-04-01	245
1994-07-01	240
1994-10-01	690
1995-01-01	-513
1995-04-01	21
1995-07-01	630
1995-10-01	192
1996-01-01	875
1996-04-01	607
1996-07-01	-878
1996-10-01	236
1997-01-01	131
1997-04-01	149
1997-07-01	165
1997-10-01	-102
1998-01-01	476
1998-04-01	827
1998-07-01	-724
1998-10-01	-1091
1999-01-01	-444
1999-04-01	314
1999-07-01	-473
1999-10-01	311
2000-01-01	337
2000-04-01	336
2000-07-01	-217
2000-10-01	-212
2001-01-01	-190
2001-04-01	-580
2001-07-01	-118
2001-10-01	-134
2002-01-01	49
2002-04-01	-107
2002-07-01	-113
2002-10-01	-64
2003-01-01	627
2003-04-01	156
2003-07-01	165
2003-10-01	-161
2004-01-01	372
2004-04-01	1
2004-07-01	207
2004-10-01	323
2005-01-01	820
2005-04-01	-194
2005-07-01	401
2005-10-01	675
2006-01-01	215
2006-04-01	-256
2006-07-01	82
2006-10-01	-475
2007-01-01	685
2007-04-01	1037
2007-07-01	919
2007-10-01	358
2008-01-01	581
2008-04-01	320
2008-07-01	647
2008-10-01	-799
2009-01-01	-551
2009-04-01	1616
2009-07-01	-315
2009-10-01	-175
2010-01-01	-22
2010-04-01	-198
2010-07-01	7
2010-10-01	-581
2011-01-01	-209
2011-04-01	1637
2011-07-01	431
2011-10-01	1023
2012-01-01	377
2012-04-01	626
2012-07-01	39
2012-10-01	842
2013-01-01	887
2013-04-01	-1395
2013-07-01	-231
2013-10-01	-225
2014-01-01	18
2014-04-01	-1579
2014-07-01	1213
2014-10-01	-1
2015-01-01	1717
2015-04-01	614
2015-07-01	-307
2015-10-01	-228
2016-01-01	55
2016-04-01	-265
2016-07-01	-136
2016-10-01	417
2017-01-01	1895
2017-04-01	-73
2017-07-01	-1403
2017-10-01	661
2018-01-01	-1382
2018-04-01	769