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	1622
1997-07-01	1581
1997-10-01	1532
1998-01-01	1512
1998-04-01	1496
1998-07-01	1540
1998-10-01	1660
1999-01-01	1604
1999-04-01	929
1999-07-01	980
1999-10-01	974
2000-01-01	872
2000-04-01	871
2000-07-01	842
2000-10-01	1126
2001-01-01	1162
2001-04-01	1778
2001-07-01	1890
2001-10-01	1705
2002-01-01	1695
2002-04-01	2296
2002-07-01	2277
2002-10-01	2854
2003-01-01	2946
2003-04-01	3065
2003-07-01	3934
2003-10-01	4027
2004-01-01	3923
2004-04-01	3727
2004-07-01	3797
2004-10-01	4064
2005-01-01	3902
2005-04-01	4245
2005-07-01	4235
2005-10-01	4418
2006-01-01	4509
2006-04-01	4645
2006-07-01	4634
2006-10-01	4860
2007-01-01	4910
2007-04-01	4564
2007-07-01	4743
2007-10-01	4658
2008-01-01	4966
2008-04-01	5192
2008-07-01	4753
2008-10-01	4130
2009-01-01	3933
2009-04-01	4178
2009-07-01	4330
2009-10-01	4309
2010-01-01	5412
2010-04-01	4965
2010-07-01	4550
2010-10-01	4512
2011-01-01	4835
2011-04-01	7138
2011-07-01	6693
2011-10-01	6213
2012-01-01	9848
2012-04-01	8588
2012-07-01	9694
2012-10-01	11805
2013-01-01	13054
2013-04-01	13217
2013-07-01	15515
2013-10-01	16895
2014-01-01	18797
2014-04-01	20358
2014-07-01	19289
2014-10-01	20650
2015-01-01	17939
2015-04-01	17821
2015-07-01	19831
2015-10-01	20333
2016-01-01	21412
2016-04-01	21604
2016-07-01	21665
2016-10-01	23023
2017-01-01	23219
2017-04-01	25675
2017-07-01	26239
2017-10-01	27710
2018-01-01	30708
2018-04-01	27639