Quarter	Millions of US Dollars
2007-10-01	19199
2008-01-01	26943
2008-04-01	24438
2008-07-01	21438
2008-10-01	17778
2009-01-01	17327
2009-04-01	15892
2009-07-01	17609
2009-10-01	18762
2010-01-01	21861
2010-04-01	21134
2010-07-01	26276
2010-10-01	25263
2011-01-01	25481
2011-04-01	23082
2011-07-01	23036
2011-10-01	23918
2012-01-01	28684
2012-04-01	27378
2012-07-01	29021
2012-10-01	31564
2013-01-01	34404
2013-04-01	32051
2013-07-01	29315
2013-10-01	26428
2014-01-01	24924
2014-04-01	26115
2014-07-01	26314
2014-10-01	26474
2015-01-01	27699
2015-04-01	26940
2015-07-01	27874
2015-10-01	25780
2016-01-01	27193
2016-04-01	28835
2016-07-01	32318
2016-10-01	33892
2017-01-01	39538
2017-04-01	39722
2017-07-01	46579
2017-10-01	45825
2018-01-01	46834