Quarter	Millions of US Dollars
1988-04-01	70560
1988-07-01	74014
1988-10-01	80754
1989-01-01	84043
1989-04-01	83646
1989-07-01	91297
1989-10-01	92132
1990-01-01	87424
1990-04-01	94691
1990-07-01	102720
1990-10-01	94184
1991-01-01	99069
1991-04-01	97882
1991-07-01	97543
1991-10-01	90281
1992-01-01	93441
1992-04-01	91678
1992-07-01	86719
1992-10-01	82235
1993-01-01	82767
1993-04-01	75692
1993-07-01	71690
1993-10-01	75650
1994-01-01	81709
1994-04-01	85173
1994-07-01	86373
1994-10-01	91992
1995-01-01	88957
1995-04-01	85680
1995-07-01	96256
1995-10-01	99340
1996-01-01	107350
1996-04-01	110271
1996-07-01	112218
1996-10-01	118653
1997-01-01	116262
1997-04-01	116151
1997-07-01	116225
1997-10-01	106773
1998-01-01	109450
1998-04-01	109639
1998-07-01	109858
1998-10-01	120867
1999-01-01	128019
1999-04-01	140341
1999-07-01	144631
1999-10-01	150937
2000-01-01	144276
2000-04-01	145136
2000-07-01	131503
2000-10-01	132800
2001-01-01	121107
2001-04-01	126885
2001-07-01	125401
2001-10-01	135534
2002-01-01	146676
2002-04-01	156926
2002-07-01	158929
2002-10-01	162948
2003-01-01	177821
2003-04-01	205493
2003-07-01	218067
2003-10-01	253354
2004-01-01	271387
2004-04-01	250294
2004-07-01	272417
2004-10-01	309576
2005-01-01	322070
2005-04-01	327150
2005-07-01	329909
2005-10-01	331853
2006-01-01	332809
2006-04-01	368268
2006-07-01	380782
2006-10-01	416413
2007-01-01	438946
2007-04-01	491953
2007-07-01	591007
2007-10-01	639690
2008-01-01	693131
2008-04-01	764612
2008-07-01	647637
2008-10-01	598699
2009-01-01	573158
2009-04-01	661989
2009-07-01	715893
2009-10-01	724182
2010-01-01	708495
2010-04-01	651818
2010-07-01	736446
2010-10-01	787808
2011-01-01	789724
2011-04-01	826074
2011-07-01	768690
2011-10-01	797361
2012-01-01	857335
2012-04-01	836620
2012-07-01	864127
2012-10-01	835432
2013-01-01	822408
2013-04-01	743389
2013-07-01	744140
2013-10-01	726059
2014-01-01	763242
2014-04-01	799681
2014-07-01	763070
2014-10-01	742279
2015-01-01	697413
2015-04-01	709072
2015-07-01	650399
2015-10-01	681093
2016-01-01	726289
2016-04-01	706701
2016-07-01	724970
2016-10-01	676794
2017-01-01	726489
2017-04-01	718948
2017-07-01	724758
2017-10-01	729370
2018-01-01	724861