Quarter	Millions of US Dollars
1987-04-01	11532
1987-07-01	12138
1987-10-01	14401
1988-01-01	15361
1988-04-01	17385
1988-07-01	19302
1988-10-01	25515
1989-01-01	26103
1989-04-01	34717
1989-07-01	35058
1989-10-01	32432
1990-01-01	34959
1990-04-01	34501
1990-07-01	38051
1990-10-01	33264
1991-01-01	34464
1991-04-01	39533
1991-07-01	45148
1991-10-01	45805
1992-01-01	49308
1992-04-01	60804
1992-07-01	57628
1992-10-01	61351
1993-01-01	63161
1993-04-01	68433
1993-07-01	69003
1993-10-01	68596
1994-01-01	72250
1994-04-01	70552
1994-07-01	67644
1994-10-01	78075
1995-01-01	81315
1995-04-01	84937
1995-07-01	74180
1995-10-01	86709
1996-01-01	87608
1996-04-01	96042
1996-07-01	102849
1996-10-01	110162
1997-01-01	114906
1997-04-01	110518
1997-07-01	106554
1997-10-01	105768
1998-01-01	111868
1998-04-01	110802
1998-07-01	119657
1998-10-01	125232
1999-01-01	121463
1999-04-01	119255
1999-07-01	121157
1999-10-01	126451
2000-01-01	135408
2000-04-01	133019
2000-07-01	129939
2000-10-01	123388
2001-01-01	130161
2001-04-01	122403
2001-07-01	125285
2001-10-01	124292
2002-01-01	131862
2002-04-01	138818
2002-07-01	136945
2002-10-01	141232
2003-01-01	146050
2003-04-01	149080
2003-07-01	157111
2003-10-01	161828
2004-01-01	173672
2004-04-01	172573
2004-07-01	174702
2004-10-01	191553
2005-01-01	194575
2005-04-01	197164
2005-07-01	187866
2005-10-01	192245
2006-01-01	198131
2006-04-01	200672
2006-07-01	195127
2006-10-01	201162
2007-01-01	197784
2007-04-01	199079
2007-07-01	197153
2007-10-01	199372
2008-01-01	218283
2008-04-01	222818
2008-07-01	208061
2008-10-01	205285
2009-01-01	202187
2009-04-01	208986
2009-07-01	210141
2009-10-01	217767
2010-01-01	226226
2010-04-01	225330
2010-07-01	232209
2010-10-01	257969
2011-01-01	258804
2011-04-01	269100
2011-07-01	258003
2011-10-01	267008
2012-01-01	279336
2012-04-01	288050
2012-07-01	299965
2012-10-01	310867
2013-01-01	313580
2013-04-01	314731
2013-07-01	324794
2013-10-01	327139
2014-01-01	325818
2014-04-01	340332
2014-07-01	332850
2014-10-01	327467
2015-01-01	336123
2015-04-01	341209
2015-07-01	320357
2015-10-01	320532
2016-01-01	329719
2016-04-01	333344
2016-07-01	338541
2016-10-01	326506
2017-01-01	358362
2017-04-01	359448
2017-07-01	359511
2017-10-01	369484
2018-01-01	379499