Quarter	Millions of US Dollars
1975-01-01	60
1975-04-01	100
1975-07-01	100
1975-10-01	100
1976-01-01	100
1976-04-01	100
1976-07-01	100
1976-10-01	100
1977-01-01	100
1977-04-01	100
1977-07-01	100
1977-10-01	100
1978-01-01	100
1978-04-01	100
1978-07-01	100
1978-10-01	100
1979-01-01	100
1979-04-01	100
1979-07-01	100
1979-10-01	100
1980-01-01	100
1980-04-01	100
1980-07-01	100
1980-10-01	100
1981-01-01	100
1981-04-01	100
1981-07-01	100
1981-10-01	100
1982-01-01	100
1982-04-01	100
1982-07-01	100
1982-10-01	100
1983-01-01	40
1996-01-01	50
1996-04-01	749
1996-07-01	741
1996-10-01	979
1997-01-01	1024
1997-04-01	1423
1997-07-01	1377
1997-10-01	1326
1998-01-01	1303
1998-04-01	1282
1998-07-01	1324
1998-10-01	1440
1999-01-01	1380
1999-04-01	701
1999-07-01	749
1999-10-01	740
2000-01-01	634
2000-04-01	628
2000-07-01	596
2000-10-01	876
2001-01-01	908
2001-04-01	1519
2001-07-01	1627
2001-10-01	1438
2002-01-01	1424
2002-04-01	2020
2002-07-01	1997
2002-10-01	2569
2003-01-01	2657
2003-04-01	2771
2003-07-01	3635
2003-10-01	3724
2004-01-01	3614
2004-04-01	3413
2004-07-01	3478
2004-10-01	3741
2005-01-01	3574
2005-04-01	3911
2005-07-01	3895
2005-10-01	3421
2006-01-01	3505
2006-04-01	3627
2006-07-01	3612
2006-10-01	3542
2007-01-01	3581
2007-04-01	3584
2007-07-01	3761
2007-10-01	3680
2008-01-01	3953
2008-04-01	4177
2008-07-01	3790
2008-10-01	3688
2009-01-01	3527
2009-04-01	3746
2009-07-01	3880
2009-10-01	3818
2010-01-01	4920
2010-04-01	4479
2010-07-01	4026
2010-10-01	3942
2011-01-01	4191
2011-04-01	6432
2011-07-01	6009
2011-10-01	5758
2012-01-01	9199
2012-04-01	7977
2012-07-01	9074
2012-10-01	11172
2013-01-01	12438
2013-04-01	12603
2013-07-01	14884
2013-10-01	16478
2014-01-01	18475
2014-04-01	20072
2014-07-01	19024
2014-10-01	20414
2015-01-01	17783
2015-04-01	17665
2015-07-01	19673
2015-10-01	20617
2016-01-01	21729
2016-04-01	21913
2016-07-01	21988
2016-10-01	23328
2017-01-01	23537
2017-04-01	26641
2017-07-01	27239
2017-10-01	29326
2018-01-01	33046
2018-04-01	29849