Quarter	Millions of US Dollars
1989-10-01	32229
1990-01-01	35803
1990-04-01	40553
1990-07-01	44475
1990-10-01	46832
1991-01-01	42005
1991-04-01	41186
1991-07-01	43485
1991-10-01	46349
1992-01-01	45337
1992-04-01	49154
1992-07-01	48355
1992-10-01	40886
1993-01-01	40255
1993-04-01	36027
1993-07-01	34338
1993-10-01	31773
1994-01-01	32276
1994-04-01	32909
1994-07-01	33389
1994-10-01	30184
1995-01-01	30043
1995-04-01	30299
1995-07-01	29362
1995-10-01	28051
1996-01-01	26690
1996-04-01	25888
1996-07-01	24269
1996-10-01	23019
1997-01-01	20700
1997-04-01	19254
1997-07-01	18810
1997-10-01	18338
1998-01-01	17940
1998-04-01	17527
1998-07-01	19256
1998-10-01	18599
1999-01-01	18195
1999-04-01	17407
1999-07-01	19454
1999-10-01	19004
2000-01-01	14750
2000-04-01	15744
2000-07-01	12771
2000-10-01	12920
2001-01-01	12492
2001-04-01	12340
2001-07-01	13422
2001-10-01	12585
2002-01-01	12437
2002-04-01	13270
2002-07-01	12831
2002-10-01	12567
2003-01-01	12824
2003-04-01	13189
2003-07-01	13503
2003-10-01	13702
2004-01-01	14509
2004-04-01	14223
2004-07-01	14290
2004-10-01	14601
2005-01-01	15301
2005-04-01	14137
2005-07-01	13165
2005-10-01	12520
2006-01-01	13282
2006-04-01	13999
2006-07-01	14271
2006-10-01	15285
2007-01-01	14412
2007-04-01	15739
2007-07-01	17927
2007-10-01	18869
2008-01-01	19877
2008-04-01	20553
2008-07-01	18893
2008-10-01	20114
2009-01-01	18065
2009-04-01	16488
2009-07-01	18817
2009-10-01	20980
2010-01-01	18865
2010-04-01	17007
2010-07-01	19330
2010-10-01	18514
2011-01-01	19785
2011-04-01	20470
2011-07-01	19509
2011-10-01	18679
2012-01-01	20493
2012-04-01	20482
2012-07-01	20530
2012-10-01	21701
2013-01-01	22014
2013-04-01	24889
2013-07-01	27226
2013-10-01	27705
2014-01-01	29872
2014-04-01	30967
2014-07-01	28456
2014-10-01	25540
2015-01-01	25576
2015-04-01	27463
2015-07-01	27808
2015-10-01	28733
2016-01-01	29786
2016-04-01	32169
2016-07-01	31494
2016-10-01	31366
2017-01-01	34630
2017-04-01	37617
2017-07-01	41619
2017-10-01	43742
2018-01-01	51411