Quarter	Millions of US Dollars
1987-04-01	5064
1987-07-01	5029
1987-10-01	6866
1988-01-01	7468
1988-04-01	8888
1988-07-01	9628
1988-10-01	13606
1989-01-01	15043
1989-04-01	13764
1989-07-01	12966
1989-10-01	9815
1990-01-01	8055
1990-04-01	7739
1990-07-01	7503
1990-10-01	7622
1991-01-01	10541
1991-04-01	12290
1991-07-01	17532
1991-10-01	18007
1992-01-01	21642
1992-04-01	31613
1992-07-01	24531
1992-10-01	24855
1993-01-01	25789
1993-04-01	25079
1993-07-01	25821
1993-10-01	28253
1994-01-01	30072
1994-04-01	28000
1994-07-01	28050
1994-10-01	30915
1995-01-01	31789
1995-04-01	30532
1995-07-01	30215
1995-10-01	31958
1996-01-01	32285
1996-04-01	31110
1996-07-01	34264
1996-10-01	36747
1997-01-01	37741
1997-04-01	36303
1997-07-01	34638
1997-10-01	32159
1998-01-01	32480
1998-04-01	30344
1998-07-01	31053
1998-10-01	34053
1999-01-01	35309
1999-04-01	36233
1999-07-01	40466
1999-10-01	44480
2000-01-01	48403
2000-04-01	47836
2000-07-01	46886
2000-10-01	46080
2001-01-01	50627
2001-04-01	49055
2001-07-01	52184
2001-10-01	54436
2002-01-01	58687
2002-04-01	64404
2002-07-01	66143
2002-10-01	68897
2003-01-01	73355
2003-04-01	73864
2003-07-01	76730
2003-10-01	77913
2004-01-01	83381
2004-04-01	82844
2004-07-01	85359
2004-10-01	93786
2005-01-01	97290
2005-04-01	98648
2005-07-01	94283
2005-10-01	97051
2006-01-01	99606
2006-04-01	102760
2006-07-01	102880
2006-10-01	104647
2007-01-01	104150
2007-04-01	107544
2007-07-01	106401
2007-10-01	109371
2008-01-01	122205
2008-04-01	126000
2008-07-01	116863
2008-10-01	117031
2009-01-01	119904
2009-04-01	126423
2009-07-01	127034
2009-10-01	130908
2010-01-01	135370
2010-04-01	135671
2010-07-01	140362
2010-10-01	156924
2011-01-01	155492
2011-04-01	162573
2011-07-01	153058
2011-10-01	159265
2012-01-01	163291
2012-04-01	166219
2012-07-01	170132
2012-10-01	176585
2013-01-01	175860
2013-04-01	175924
2013-07-01	180693
2013-10-01	181901
2014-01-01	179346
2014-04-01	186296
2014-07-01	179712
2014-10-01	175932
2015-01-01	178230
2015-04-01	181988
2015-07-01	169161
2015-10-01	172154
2016-01-01	176940
2016-04-01	177582
2016-07-01	179119
2016-10-01	175656
2017-01-01	189134
2017-04-01	188279
2017-07-01	185481
2017-10-01	190913
2018-01-01	193828