Quarter	Millions of US Dollars
1989-01-01	51547
1989-04-01	51492
1989-07-01	53817
1989-10-01	55387
1990-01-01	55825
1990-04-01	59662
1990-07-01	60059
1990-10-01	55178
1991-01-01	52720
1991-04-01	49335
1991-07-01	50887
1991-10-01	47006
1992-01-01	36862
1992-04-01	38997
1992-07-01	36104
1992-10-01	28696
1993-01-01	27339
1993-04-01	31472
1993-07-01	32415
1993-10-01	35478
1994-01-01	34330
1994-04-01	35300
1994-07-01	37447
1994-10-01	34672
1995-01-01	38667
1995-04-01	40349
1995-07-01	42239
1995-10-01	41952
1996-01-01	44125
1996-04-01	45599
1996-07-01	47490
1996-10-01	49253
1997-01-01	55009
1997-04-01	59027
1997-07-01	62223
1997-10-01	65455
1998-01-01	71845
1998-04-01	78372
1998-07-01	78932
1998-10-01	79353
1999-01-01	87690
1999-04-01	90476
1999-07-01	92824
1999-10-01	99860
2000-01-01	105646
2000-04-01	104884
2000-07-01	104270
2000-10-01	105969
2001-01-01	100339
2001-04-01	99977
2001-07-01	95925
2001-10-01	94434
2002-01-01	90754
2002-04-01	95522
2002-07-01	90204
2002-10-01	88963
2003-01-01	94761
2003-04-01	99891
2003-07-01	97790
2003-10-01	100344
2004-01-01	99167
2004-04-01	98411
2004-07-01	104032
2004-10-01	112927
2005-01-01	117573
2005-04-01	119141
2005-07-01	132050
2005-10-01	138373
2006-01-01	151850
2006-04-01	164838
2006-07-01	171667
2006-10-01	177810
2007-01-01	183614
2007-04-01	204701
2007-07-01	192244
2007-10-01	180424
2008-01-01	169311
2008-04-01	154115
2008-07-01	138125
2008-10-01	112614
2009-01-01	102824
2009-04-01	106292
2009-07-01	104271
2009-10-01	92034
2010-01-01	93020
2010-04-01	90538
2010-07-01	89413
2010-10-01	88430
2011-01-01	93778
2011-04-01	94816
2011-07-01	91954
2011-10-01	91020
2012-01-01	101978
2012-04-01	99283
2012-07-01	106168
2012-10-01	99801
2013-01-01	98721
2013-04-01	99600
2013-07-01	100970
2013-10-01	97002
2014-01-01	99432
2014-04-01	105139
2014-07-01	102101
2014-10-01	95201
2015-01-01	92440
2015-04-01	99169
2015-07-01	86987
2015-10-01	84896
2016-01-01	87781
2016-04-01	95597
2016-07-01	98452
2016-10-01	89181
2017-01-01	91803
2017-04-01	98945
2017-07-01	106828
2017-10-01	100960
2018-01-01	101256