Quarter	Millions of US Dollars
2003-01-01	11957
2003-04-01	12310
2003-07-01	13872
2003-10-01	15099
2004-01-01	15248
2004-04-01	14956
2004-07-01	14775
2004-10-01	16197
2005-01-01	15875
2005-04-01	15495
2005-07-01	15999
2005-10-01	17666
2006-01-01	18913
2006-04-01	21538
2006-07-01	22733
2006-10-01	24001
2007-01-01	26347
2007-04-01	28651
2007-07-01	29508
2007-10-01	30950
2008-01-01	29658
2008-04-01	28362
2008-07-01	28967
2008-10-01	29156
2009-01-01	29826
2009-04-01	33435
2009-07-01	35665
2009-10-01	35390
2010-01-01	36858
2010-04-01	37151
2010-07-01	39415
2010-10-01	40649
2011-01-01	41235
2011-04-01	40737
2011-07-01	40353
2011-10-01	40024
2012-01-01	43999
2012-04-01	41919
2012-07-01	44672
2012-10-01	45740
2013-01-01	49481
2013-04-01	47468
2013-07-01	48592
2013-10-01	47607
2014-01-01	51012
2014-04-01	52870
2014-07-01	55715
2014-10-01	56329
2015-01-01	58417
2015-04-01	59370
2015-07-01	57952
2015-10-01	59534
2016-01-01	72326
2016-04-01	74371
2016-07-01	76089
2016-10-01	69947
2017-01-01	74009
2017-04-01	76966
2017-07-01	79171
2017-10-01	80795
2018-01-01	86542