Quarter	Millions of US Dollars
1996-10-01	1200
1997-01-01	1200
1997-04-01	1200
1997-07-01	1200
1997-10-01	1200
1998-01-01	1200
1998-04-01	1200
1998-07-01	1200
1998-10-01	1200
1999-01-01	1200
1999-04-01	1200
1999-07-01	1200
1999-10-01	1200
2000-01-01	1200
2000-04-01	1200
2000-07-01	1200
2000-10-01	1200
2001-01-01	1200
2001-04-01	1200
2001-07-01	1200
2001-10-01	1200
2002-01-01	1127
2002-04-01	1127
2002-07-01	1091
2002-10-01	1091
2003-01-01	1055
2003-04-01	1055
2003-07-01	1055
2003-10-01	1055
2004-01-01	1647
2004-04-01	1647
2004-07-01	1610
2004-10-01	1610
2005-01-01	1574
2005-04-01	1574
2005-07-01	3788
2005-10-01	3788
2006-01-01	3751
2006-04-01	4401
2006-07-01	5915
2006-10-01	5915
2007-01-01	5915
2007-04-01	5915
2007-07-01	5915
2007-10-01	5915
2008-01-01	5915
2008-04-01	5915
2008-07-01	5915
2008-10-01	5915
2009-01-01	5915
2009-04-01	5915
2009-07-01	7400
2009-10-01	7400
2010-01-01	7320
2010-04-01	7320
2010-07-01	7240
2010-10-01	7186
2011-01-01	7106
2011-04-01	6456
2011-07-01	6376
2011-10-01	6376
2012-01-01	6296
2012-04-01	6296
2012-07-01	6811
2012-10-01	6703
2013-01-01	6616
2013-04-01	6575
2013-07-01	6427
2013-10-01	6366
2014-01-01	6379
2014-04-01	6394
2014-07-01	5135
2014-10-01	5071
2015-01-01	5070
2015-04-01	5055
2015-07-01	5068
2015-10-01	5067
2016-01-01	5117
2016-04-01	5188
2016-07-01	4450
2016-10-01	4337
2017-01-01	4371
2017-04-01	4870
2017-07-01	4866
2017-10-01	4866
2018-01-01	4909
2018-04-01	4879