Quarter	Millions of US Dollars
1997-01-01	0
1997-04-01	0
1997-07-01	0
1997-10-01	48
1998-01-01	46
1998-04-01	45
1998-07-01	49
1998-10-01	0
1999-01-01	0
1999-04-01	0
1999-07-01	0
1999-10-01	0
2000-01-01	86
2000-04-01	86
2000-07-01	79
2000-10-01	84
2001-01-01	300
2001-04-01	343
2001-07-01	346
2001-10-01	345
2002-01-01	44
2002-04-01	0
2002-07-01	0
2002-10-01	0
2003-01-01	38
2003-04-01	38
2003-07-01	253
2003-10-01	505
2004-01-01	1077
2004-04-01	1183
2004-07-01	847
2004-10-01	681
2005-01-01	623
2005-04-01	588
2005-07-01	1464
2005-10-01	1442
2006-01-01	883
2006-04-01	897
2006-07-01	339
2006-10-01	336
2007-01-01	998
2007-04-01	1187
2007-07-01	919
2007-10-01	925
2008-01-01	1123
2008-04-01	1106
2008-07-01	1031
2008-10-01	1258
2009-01-01	1197
2009-04-01	997
2009-07-01	1030
2009-10-01	798
2010-01-01	1454
2010-04-01	1327
2010-07-01	1433
2010-10-01	1403
2011-01-01	0
2011-04-01	0
2011-07-01	0
2011-10-01	129
2012-01-01	134
2012-04-01	126
2012-07-01	129
2012-10-01	0
2013-01-01	0
2013-04-01	1177
2013-07-01	1215
2013-10-01	1241
2014-01-01	2275
2014-04-01	1024
2014-07-01	944
2014-10-01	954
2015-01-01	38
2015-04-01	72
2015-07-01	261
2015-10-01	410
2016-01-01	429
2016-04-01	2211
2016-07-01	2406
2016-10-01	2667
2017-01-01	2676
2017-04-01	966
2017-07-01	1385
2017-10-01	899
2018-01-01	924
2018-04-01	1224