Quarter	Millions of US Dollars
1988-04-01	196929
1988-07-01	204352
1988-10-01	227185
1989-01-01	224605
1989-04-01	213877
1989-07-01	230749
1989-10-01	243419
1990-01-01	237304
1990-04-01	243686
1990-07-01	265225
1990-10-01	256805
1991-01-01	267223
1991-04-01	261213
1991-07-01	277560
1991-10-01	275422
1992-01-01	278719
1992-04-01	281562
1992-07-01	274474
1992-10-01	270504
1993-01-01	279272
1993-04-01	268136
1993-07-01	268945
1993-10-01	285518
1994-01-01	295342
1994-04-01	296891
1994-07-01	300610
1994-10-01	319853
1995-01-01	308575
1995-04-01	314520
1995-07-01	339394
1995-10-01	340749
1996-01-01	359817
1996-04-01	367168
1996-07-01	383039
1996-10-01	393531
1997-01-01	386193
1997-04-01	376754
1997-07-01	376822
1997-10-01	344947
1998-01-01	351620
1998-04-01	334210
1998-07-01	334474
1998-10-01	346242
1999-01-01	365609
1999-04-01	376811
1999-07-01	384311
1999-10-01	393361
2000-01-01	378941
2000-04-01	381261
2000-07-01	357070
2000-10-01	367057
2001-01-01	338005
2001-04-01	347153
2001-07-01	352840
2001-10-01	364352
2002-01-01	383665
2002-04-01	408747
2002-07-01	415219
2002-10-01	430767
2003-01-01	459577
2003-04-01	519654
2003-07-01	539726
2003-10-01	609924
2004-01-01	647850
2004-04-01	612807
2004-07-01	661292
2004-10-01	732628
2005-01-01	741861
2005-04-01	752702
2005-07-01	757982
2005-10-01	770002
2006-01-01	789169
2006-04-01	846863
2006-07-01	885650
2006-10-01	956735
2007-01-01	1003863
2007-04-01	1090703
2007-07-01	1217132
2007-10-01	1250016
2008-01-01	1362299
2008-04-01	1467228
2008-07-01	1266863
2008-10-01	1140259
2009-01-01	1134052
2009-04-01	1342728
2009-07-01	1449467
2009-10-01	1521081
2010-01-01	1541695
2010-04-01	1470184
2010-07-01	1652964
2010-10-01	1737958
2011-01-01	1782850
2011-04-01	1860992
2011-07-01	1791281
2011-10-01	1869478
2012-01-01	1975818
2012-04-01	1952935
2012-07-01	2035591
2012-10-01	2030704
2013-01-01	2032545
2013-04-01	1859457
2013-07-01	1902221
2013-10-01	1872585
2014-01-01	1955059
2014-04-01	2040955
2014-07-01	1949505
2014-10-01	1911667
2015-01-01	1832336
2015-04-01	1850641
2015-07-01	1754018
2015-10-01	1819471
2016-01-01	1929138
2016-04-01	1884973
2016-07-01	1929955
2016-10-01	1814296
2017-01-01	1909727
2017-04-01	1934203
2017-07-01	1966452
2017-10-01	1989067
2018-01-01	2000302