Quarter	Millions of US Dollars
1990-04-01	150
1990-07-01	150
1990-10-01	150
1991-01-01	150
1991-04-01	150
1991-07-01	150
1991-10-01	150
1992-01-01	150
1992-04-01	150
1992-07-01	150
1992-10-01	150
1993-01-01	150
1993-04-01	150
1993-07-01	150
1993-10-01	150
1994-01-01	150
1994-04-01	150
1994-07-01	150
1994-10-01	150
1995-01-01	150
1995-04-01	150
1995-07-01	150
1995-10-01	150
1996-01-01	150
1996-04-01	150
1996-07-01	150
1996-10-01	150
1997-01-01	150
1997-04-01	150
1997-07-01	150
1997-10-01	150
1998-01-01	250
1998-04-01	250
1998-07-01	250
1998-10-01	250
1999-01-01	250
1999-04-01	250
1999-07-01	250
1999-10-01	250
2000-01-01	250
2000-04-01	250
2000-07-01	250
2000-10-01	250
2001-01-01	250
2001-04-01	250
2001-07-01	250
2001-10-01	250
2002-01-01	250
2002-04-01	100
2002-07-01	100
2002-10-01	100
2003-01-01	100
2003-04-01	100
2003-07-01	100
2003-10-01	100
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	250
2007-07-01	250
2007-10-01	250
2008-01-01	150
2008-04-01	150
2008-07-01	150
2008-10-01	150
2009-01-01	150
2009-04-01	150
2009-07-01	150
2009-10-01	150
2010-01-01	150
2010-04-01	150
2010-07-01	150
2010-10-01	150
2011-01-01	150
2011-04-01	165
2011-07-01	215
2011-10-01	215
2012-01-01	215
2012-04-01	540
2012-07-01	787
2012-10-01	841
2013-01-01	1129
2013-04-01	1309
2013-07-01	1478
2013-10-01	1702
2014-01-01	1684
2014-04-01	1596
2014-07-01	1192
2014-10-01	1177
2015-01-01	1169
2015-04-01	1076
2015-07-01	1090
2015-10-01	1102
2016-01-01	1102
2016-04-01	1209
2016-07-01	1232
2016-10-01	1220
2017-01-01	1344
2017-04-01	1430
2017-07-01	1327
2017-10-01	1203
2018-01-01	703
2018-04-01	604