Quarter	Millions of US Dollars
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	0
1981-07-01	0
1981-10-01	0
1982-01-01	0
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	20
1984-04-01	20
1984-07-01	20
1984-10-01	40
1985-01-01	20
1985-04-01	20
1985-07-01	20
1998-04-01	0
1998-07-01	0
1998-10-01	0
1999-01-01	0
1999-04-01	0
1999-07-01	0
1999-10-01	0
2000-01-01	0
2000-04-01	0
2000-07-01	0
2000-10-01	0
2001-01-01	0
2001-04-01	0
2001-07-01	0
2001-10-01	0
2002-01-01	0
2002-04-01	200
2002-07-01	200
2002-10-01	200
2003-01-01	200
2003-04-01	0
2003-07-01	0
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	200
2007-04-01	200
2007-07-01	200
2007-10-01	200
2008-01-01	0
2008-04-01	300
2008-07-01	300
2008-10-01	300
2009-01-01	300
2009-04-01	0
2009-07-01	0
2009-10-01	0
2010-01-01	250
2010-04-01	250
2010-07-01	250
2010-10-01	250
2011-01-01	250
2011-04-01	250
2011-07-01	250
2011-10-01	250
2012-01-01	250
2012-04-01	250
2012-07-01	250
2012-10-01	250
2013-01-01	250
2013-04-01	250
2013-07-01	250
2013-10-01	250
2014-01-01	0
2014-04-01	0
2014-07-01	0
2014-10-01	0
2015-01-01	0
2015-04-01	0
2015-07-01	0
2015-10-01	0
2016-01-01	0
2016-04-01	0
2016-07-01	0
2016-10-01	0
2017-01-01	0
2017-04-01	0
2017-07-01	0
2017-10-01	0
2018-01-01	0
2018-04-01	0