Quarter	Millions of US Dollars
2001-10-01	5331
2002-01-01	1760
2002-04-01	4038
2002-07-01	4537
2002-10-01	4260
2003-01-01	4575
2003-04-01	5098
2003-07-01	5728
2003-10-01	5785
2004-01-01	6851
2004-04-01	7816
2004-07-01	7822
2004-10-01	8259
2005-01-01	8459
2005-04-01	10531
2005-07-01	11736
2005-10-01	11338
2006-01-01	11933
2006-04-01	12918
2006-07-01	14646
2006-10-01	15695
2007-01-01	18763
2007-04-01	22479
2007-07-01	20976
2007-10-01	18771
2008-01-01	20317
2008-04-01	18879
2008-07-01	18252
2008-10-01	13026
2009-01-01	11317
2009-04-01	10817
2009-07-01	12458
2009-10-01	13532
2010-01-01	13958
2010-04-01	15490
2010-07-01	18786
2010-10-01	19240
2011-01-01	21499
2011-04-01	23264
2011-07-01	20615
2011-10-01	17563
2012-01-01	19872
2012-04-01	20668
2012-07-01	20304
2012-10-01	18480
2013-01-01	21146
2013-04-01	20056
2013-07-01	20431
2013-10-01	17433
2014-01-01	19385
2014-04-01	23574
2014-07-01	27457
2014-10-01	29802
2015-01-01	33968
2015-04-01	35939
2015-07-01	34578
2015-10-01	28055
2016-01-01	34569
2016-04-01	35390
2016-07-01	42669
2016-10-01	40662
2017-01-01	47030
2017-04-01	53339
2017-07-01	60514