Quarter	Millions of US Dollars
2005-01-01	22683
2005-04-01	29278
2005-07-01	30629
2005-10-01	29831
2006-01-01	35037
2006-04-01	36688
2006-07-01	39817
2006-10-01	43622
2007-01-01	50025
2007-04-01	52688
2007-07-01	49333
2007-10-01	52155
2008-01-01	59934
2008-04-01	63499
2008-07-01	56420
2008-10-01	48187
2009-01-01	43158
2009-04-01	46059
2009-07-01	41102
2009-10-01	38976
2010-01-01	39027
2010-04-01	50891
2010-07-01	56025
2010-10-01	59525
2011-01-01	64541
2011-04-01	68464
2011-07-01	72954
2011-10-01	66345
2012-01-01	76403
2012-04-01	72395
2012-07-01	77847
2012-10-01	75601
2013-01-01	69597
2013-04-01	64784
2013-07-01	61652
2013-10-01	61609
2014-01-01	59872
2014-04-01	59817
2014-07-01	69675
2014-10-01	73257
2015-01-01	58425
2015-04-01	45797
2015-07-01	37142
2015-10-01	40979
2016-01-01	42575
2016-04-01	37638
2016-07-01	34599
2016-10-01	32334
2017-01-01	32503
2017-04-01	33374
2017-07-01	33056
2017-10-01	36047
2018-01-01	37853