Quarter	Millions of US Dollars
2004-01-01	3252
2004-04-01	3661
2004-07-01	4294
2004-10-01	4868
2005-01-01	5382
2005-04-01	6494
2005-07-01	7025
2005-10-01	6504
2006-01-01	7603
2006-04-01	8878
2006-07-01	9326
2006-10-01	11141
2007-01-01	12410
2007-04-01	13406
2007-07-01	11378
2007-10-01	12046
2008-01-01	13153
2008-04-01	12573
2008-07-01	17440
2008-10-01	12434
2009-01-01	10230
2009-04-01	10295
2009-07-01	10741
2009-10-01	10016
2010-01-01	10181
2010-04-01	8633
2010-07-01	5728
2010-10-01	5859
2011-01-01	6278
2011-04-01	7994
2011-07-01	9270
2011-10-01	10287
2012-01-01	9802
2012-04-01	8665
2012-07-01	8376
2012-10-01	11417
2013-01-01	10981
2013-04-01	8752
2013-07-01	9315
2013-10-01	9982
2014-01-01	9868
2014-04-01	9615
2014-07-01	8796
2014-10-01	8609
2015-01-01	7755
2015-04-01	7890
2015-07-01	7846
2015-10-01	7009
2016-01-01	7382
2016-04-01	7138
2016-07-01	7407
2016-10-01	10791
2017-01-01	11968
2017-04-01	14542
2017-07-01	11634
2017-10-01	13426
2018-01-01	12290