Quarter	Millions of US Dollars
2004-01-01	15253
2004-04-01	17482
2004-07-01	19826
2004-10-01	22510
2005-01-01	23829
2005-04-01	27008
2005-07-01	30627
2005-10-01	35119
2006-01-01	38904
2006-04-01	41571
2006-07-01	45566
2006-10-01	54564
2007-01-01	63122
2007-04-01	72986
2007-07-01	77849
2007-10-01	81763
2008-01-01	91438
2008-04-01	96847
2008-07-01	96688
2008-10-01	89968
2009-01-01	83863
2009-04-01	95031
2009-07-01	106634
2009-10-01	113207
2010-01-01	117159
2010-04-01	113255
2010-07-01	117034
2010-10-01	123955
2011-01-01	137728
2011-04-01	148114
2011-07-01	134078
2011-10-01	135331
2012-01-01	144317
2012-04-01	134750
2012-07-01	143429
2012-10-01	154480
2013-01-01	164830
2013-04-01	175314
2013-07-01	178616
2013-10-01	181630
2014-01-01	172421
2014-04-01	172213
2014-07-01	156938
2014-10-01	138090
2015-01-01	145923
2015-04-01	147955
2015-07-01	140470
2015-10-01	131394
2016-01-01	139234
2016-04-01	144589
2016-07-01	146571
2016-10-01	162098
2017-01-01	172432
2017-04-01	175061
2017-07-01	186188
2017-10-01	196432
2018-01-01	199603