Quarter	Millions of US Dollars
1993-10-01	15
1994-01-01	70
1994-04-01	60
1994-07-01	60
1994-10-01	50
1995-01-01	50
1995-04-01	50
1995-07-01	50
1995-10-01	50
1996-01-01	50
1996-04-01	50
1996-07-01	50
1996-10-01	50
1997-10-01	8
1998-01-01	8
2003-10-01	40
2004-01-01	100
2004-04-01	100
2004-07-01	100
2004-10-01	100
2005-01-01	100
2005-04-01	100
2005-07-01	100
2005-10-01	100
2006-01-01	100
2006-04-01	100
2006-07-01	100
2006-10-01	100
2007-01-01	100
2007-04-01	100
2007-07-01	100
2007-10-01	100
2008-01-01	100
2008-04-01	100
2008-07-01	100
2008-10-01	100
2009-01-01	100
2009-04-01	100
2009-07-01	100
2009-10-01	100
2010-01-01	100
2010-04-01	100
2010-07-01	100
2010-10-01	100
2011-01-01	100
2011-04-01	100
2011-07-01	100
2011-10-01	350
2012-01-01	350
2012-04-01	600
2012-07-01	600
2012-10-01	600
2013-01-01	600
2013-04-01	1100
2013-07-01	1100
2013-10-01	1060
2014-01-01	1000
2014-04-01	1000
2014-07-01	1000
2014-10-01	1000
2015-01-01	1000
2015-04-01	1000
2015-07-01	1000
2015-10-01	1000
2016-01-01	1000
2016-04-01	1000
2016-07-01	1000
2016-10-01	1000
2017-01-01	1000
2017-04-01	1600
2017-07-01	1600
2017-10-01	1600
2018-01-01	1600
2018-04-01	1600