Quarter	Millions of US Dollars
2002-01-01	109
2002-04-01	338
2002-07-01	696
2002-10-01	957
2003-01-01	1389
2003-04-01	1967
2003-07-01	2601
2003-10-01	3042
2004-01-01	4136
2004-04-01	4524
2004-07-01	4584
2004-10-01	5005
2005-01-01	5709
2005-04-01	7851
2005-07-01	9093
2005-10-01	8618
2006-01-01	9104
2006-04-01	10208
2006-07-01	12018
2006-10-01	12921
2007-01-01	15971
2007-04-01	19114
2007-07-01	17907
2007-10-01	15831
2008-01-01	17434
2008-04-01	16047
2008-07-01	15556
2008-10-01	10607
2009-01-01	9078
2009-04-01	8678
2009-07-01	10371
2009-10-01	11562
2010-01-01	12112
2010-04-01	13866
2010-07-01	17150
2010-10-01	17760
2011-01-01	20009
2011-04-01	21286
2011-07-01	18472
2011-10-01	15421
2012-01-01	17603
2012-04-01	18285
2012-07-01	17902
2012-10-01	16085
2013-01-01	18721
2013-04-01	17502
2013-07-01	17659
2013-10-01	14615
2014-01-01	16783
2014-04-01	20973
2014-07-01	24716
2014-10-01	26914
2015-01-01	31222
2015-04-01	33222
2015-07-01	31759
2015-10-01	25501
2016-01-01	32144
2016-04-01	32912
2016-07-01	39632
2016-10-01	37207
2017-01-01	43361
2017-04-01	49044
2017-07-01	56064
2017-10-01	52857
2018-01-01	56744