Quarter	Millions of US Dollars
1976-01-01	17
1976-04-01	30
1976-10-01	35
1977-01-01	40
1977-07-01	6
1978-04-01	30
1979-04-01	25
1979-07-01	56
1981-04-01	-30
1981-10-01	-35
1982-07-01	-7
1984-04-01	-19
1985-10-01	-26
1986-01-01	-15
1986-10-01	-18
1987-04-01	-28
1987-07-01	-2
1988-04-01	-3
1989-01-01	-27
1989-07-01	-25
1994-04-01	20
1994-07-01	0
1994-10-01	5840
1995-01-01	-20
1995-07-01	250
1996-04-01	200
1996-07-01	154
1996-10-01	40
1997-04-01	130
1997-07-01	400
1998-10-01	-495
1999-01-01	-6
1999-04-01	-150
1999-10-01	-50
2000-01-01	577
2000-04-01	-57
2000-07-01	-131
2000-10-01	-944
2001-01-01	691
2001-04-01	-319
2001-07-01	-114
2001-10-01	208
2002-01-01	633
2002-04-01	-32
2002-07-01	1375
2002-10-01	-703
2003-01-01	1609
2003-04-01	-203
2003-07-01	1673
2003-10-01	1007
2004-01-01	3067
2004-04-01	1265
2005-01-01	4589
2005-04-01	7265
2005-07-01	-1055
2005-10-01	2117
2006-01-01	4208
2006-04-01	182
2006-07-01	-637
2006-10-01	723
2007-01-01	0
2007-04-01	1227
2007-07-01	-300
2007-10-01	394
2008-01-01	-777
2008-04-01	3807
2008-07-01	-210
2009-01-01	1931
2009-04-01	1726
2009-07-01	3135
2009-10-01	1832
2010-01-01	5488
2010-04-01	-360
2010-07-01	2640
2010-10-01	-1032
2011-01-01	674
2011-04-01	2000
2011-07-01	732
2011-10-01	2247
2012-01-01	3571
2012-04-01	1404
2012-07-01	2112
2012-10-01	5032
2013-01-01	-3565
2013-10-01	2514
2014-01-01	905
2014-04-01	-2349
2014-07-01	-94
2014-10-01	-181
2015-01-01	133
2015-04-01	177
2015-07-01	722
2015-10-01	-340
2016-01-01	-1535
2016-04-01	3161
2016-07-01	-1308
2016-10-01	3087
2017-01-01	-528
2017-04-01	-479
2017-07-01	1926
2017-10-01	4741
2018-01-01	1844
2018-04-01	-1705