Quarter	Millions of US Dollars
1993-07-01	1500
1993-10-01	1500
1994-01-01	1500
1994-04-01	1500
1994-07-01	1500
1994-10-01	1500
1995-01-01	1500
1995-04-01	1500
1995-07-01	1500
1995-10-01	1500
1996-01-01	1500
1996-04-01	1500
1996-07-01	1500
1996-10-01	1500
1997-01-01	1500
1997-04-01	1500
1997-07-01	1500
1997-10-01	1500
1998-01-01	1500
1998-04-01	1500
1998-07-01	1500
1998-10-01	1500
1999-01-01	1500
1999-04-01	1500
1999-07-01	1500
1999-10-01	1500
2000-01-01	1500
2000-04-01	1500
2000-07-01	1500
2000-10-01	1500
2001-01-01	1500
2001-04-01	1500
2001-07-01	1500
2001-10-01	1500
2002-01-01	1500
2002-04-01	1500
2002-07-01	1500
2002-10-01	1500
2003-01-01	1500
2003-04-01	1500
2003-07-01	1500
2003-10-01	1500
2004-01-01	2000
2004-04-01	2000
2004-07-01	2000
2004-10-01	2000
2005-01-01	2000
2005-04-01	2000
2005-07-01	2000
2005-10-01	2000
2006-01-01	2000
2006-04-01	2253
2006-07-01	2752
2006-10-01	6248
2007-01-01	6262
2007-04-01	7524
2007-07-01	11408
2007-10-01	14239
2008-01-01	15985
2008-04-01	16449
2008-07-01	18190
2008-10-01	18159
2009-01-01	18099
2009-04-01	18174
2009-07-01	22679
2009-10-01	23077
2010-01-01	23008
2010-04-01	23917
2010-07-01	24039
2010-10-01	26525
2011-01-01	26094
2011-04-01	26454
2011-07-01	26376
2011-10-01	27836
2012-01-01	29784
2012-04-01	28617
2012-07-01	28655
2012-10-01	28150
2013-01-01	29566
2013-04-01	29580
2013-07-01	28932
2013-10-01	28415
2014-01-01	28716
2014-04-01	35356
2014-07-01	32603
2014-10-01	33820
2015-01-01	33498
2015-04-01	34503
2015-07-01	34528
2015-10-01	34515
2016-01-01	35118
2016-04-01	35801
2016-07-01	35818
2016-10-01	35176
2017-01-01	34761
2017-04-01	35453
2017-07-01	35513
2017-10-01	37999
2018-01-01	37260
2018-04-01	38570