Quarter	Millions of US Dollars
1976-07-01	0
1976-10-01	0
1977-01-01	0
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	11
1979-10-01	11
1980-01-01	11
1980-04-01	11
1998-01-01	11
1998-04-01	11
1998-07-01	11
1998-10-01	11
1999-01-01	11
1999-04-01	11
1999-07-01	11
1999-10-01	11
2000-01-01	11
2000-04-01	11
2000-07-01	11
2000-10-01	11
2001-01-01	11
2001-04-01	11
2001-07-01	11
2001-10-01	11
2002-01-01	11
2002-04-01	11
2002-07-01	12
2002-10-01	12
2003-01-01	13
2003-04-01	13
2003-07-01	13
2003-10-01	13
2004-01-01	13
2004-04-01	13
2004-07-01	13
2004-10-01	13
2005-01-01	13
2005-04-01	13
2005-07-01	13
2005-10-01	13
2006-01-01	13
2006-04-01	13
2006-07-01	13
2006-10-01	13
2007-01-01	15
2007-04-01	15
2007-07-01	17
2007-10-01	17
2008-01-01	17
2008-04-01	17
2008-07-01	17
2008-10-01	17
2009-01-01	17
2009-04-01	868
2009-07-01	872
2009-10-01	872
2010-01-01	877
2010-04-01	26
2010-07-01	26
2010-10-01	26
2011-01-01	26
2011-04-01	26
2011-07-01	30
2011-10-01	30
2012-01-01	34
2012-04-01	34
2012-07-01	34
2012-10-01	34
2013-01-01	34
2013-04-01	34
2013-07-01	34
2013-10-01	34
2014-01-01	34
2014-04-01	34
2014-07-01	34
2014-10-01	34
2015-01-01	34
2015-04-01	34
2015-07-01	38
2015-10-01	38
2016-01-01	43
2016-04-01	43
2016-07-01	43
2016-10-01	43
2017-01-01	43
2017-04-01	43
2017-07-01	22
2017-10-01	22
2018-01-01	0
2018-04-01	0