Quarter	Millions of US Dollars
2001-10-01	10
2002-01-01	10
2003-01-01	9
2003-04-01	9
2003-07-01	9
2003-10-01	8
2006-01-01	16
2006-04-01	17
2006-07-01	17
2006-10-01	18
2009-10-01	432
2010-01-01	404
2010-04-01	368
2010-07-01	409
2010-10-01	401
2011-01-01	426
2011-04-01	434
2011-07-01	405
2011-10-01	388
2012-01-01	401
2012-04-01	378
2012-07-01	388
2012-10-01	396
2013-01-01	384
2013-04-01	392
2013-07-01	405
2013-10-01	414
2014-01-01	414
2014-04-01	772
2014-07-01	711
2014-10-01	686
2015-01-01	608
2015-04-01	632
2015-07-01	633
2015-10-01	615
2016-01-01	643
2016-04-01	627
2016-07-01	631
2016-10-01	279
2017-01-01	283
2017-04-01	302
2017-07-01	313
2017-10-01	318
2018-01-01	327
2018-04-01	309