Quarter	Millions of US Dollars
1977-04-01	0
1977-07-01	0
1977-10-01	0
1978-01-01	0
1978-04-01	0
1978-07-01	0
1978-10-01	0
1979-01-01	0
1979-04-01	0
1979-07-01	0
1979-10-01	0
1980-01-01	0
1980-04-01	0
1980-07-01	0
1980-10-01	0
1981-01-01	0
1981-04-01	10
1981-07-01	10
1981-10-01	10
1982-01-01	10
1982-04-01	0
1982-07-01	0
1982-10-01	0
1983-01-01	0
1983-04-01	0
1983-07-01	0
1983-10-01	0
1984-01-01	0
1984-04-01	0
1984-07-01	0
1984-10-01	0
1985-01-01	0
1985-04-01	10
1985-07-01	11
1985-10-01	12
1986-01-01	13
1986-04-01	0
1986-07-01	0
1986-10-01	200
1987-01-01	200
1987-04-01	200
1987-07-01	200
2003-10-01	0
2004-01-01	0
2004-04-01	0
2004-07-01	0
2004-10-01	0
2005-01-01	0
2005-04-01	0
2005-07-01	0
2005-10-01	0
2006-01-01	0
2006-04-01	0
2006-07-01	0
2006-10-01	0
2007-01-01	0
2007-04-01	0
2007-07-01	43
2007-10-01	1149
2008-01-01	1236
2008-04-01	1231
2008-07-01	1073
2008-10-01	0
2009-01-01	600
2009-04-01	600
2009-07-01	610
2009-10-01	1300
2010-01-01	700
2010-04-01	1700
2010-07-01	1700
2010-10-01	1000
2011-01-01	1000
2011-04-01	650
2011-07-01	1800
2011-10-01	1700
2012-01-01	2980
2012-04-01	2330
2012-07-01	1330
2012-10-01	2320
2013-01-01	960
2013-04-01	2848
2013-07-01	3055
2013-10-01	2042
2014-01-01	3345
2014-04-01	1479
2014-07-01	2811
2014-10-01	3841
2015-01-01	2546
2015-04-01	2533
2015-07-01	1038
2015-10-01	390
2016-01-01	368
2016-04-01	1615
2016-07-01	1593
2016-10-01	1266
2017-01-01	1266
2017-04-01	460
2017-07-01	460
2017-10-01	1460
2018-01-01	1525
2018-04-01	1956