Quarter	Percent
1975-03-31	9.4943
1975-06-30	9.3906
1975-09-30	10.1867
1975-12-31	11.0902
1976-03-31	9.1424
1976-06-30	10.072
1976-09-30	11.3164
1976-12-31	14.0845
1977-03-31	11.0355
1977-06-30	7.6387
1977-09-30	6.481
1977-12-31	5.3659
1978-03-31	5.9003
1978-06-30	8.1856
1978-09-30	9.0287
1978-12-31	11.0248
1979-03-31	11.9011
1979-06-30	11.8072
1979-09-30	13.3392
1979-12-31	14.9047
1980-03-31	16.0474
1980-06-30	16.0246
1980-09-30	14.6257
1980-12-31	13.7626
1981-03-31	12.201
1981-06-30	11.5693
1981-09-30	13.4819
1981-12-31	14.7494
1982-03-31	13.2718
1982-06-30	12.5787
1982-09-30	10.4163
1982-12-31	9.3448
1983-03-31	10.5701
1983-06-30	9.6096
1983-09-30	9.287
1983-12-31	8.8529
1984-03-31	8.6967
1984-06-30	8.6986
1984-09-30	10.3883
1984-12-31	9.3806
1985-03-31	12.1262
1985-06-30	11.9181
1985-09-30	11.1221
1985-12-31	11.1104
1986-03-31	11.706
1986-06-30	9.6748
1986-09-30	9.4764
1986-12-31	10.5176
1987-03-31	10.09
1987-06-30	8.7819
1987-09-30	9.3933
1987-12-31	8.7092
1988-03-31	8.47
1988-06-30	8.0301
1988-09-30	10.8437
1988-12-31	12.0051
1989-03-31	12.4138
1989-06-30	12.9324
1989-09-30	13.359
1989-12-31	14.4699
1990-03-31	14.5151
1990-06-30	14.4854
1990-09-30	14.3003
1990-12-31	13.0712
1991-03-31	12.2904
1991-06-30	10.9296
1991-09-30	10.1349
1991-12-31	9.9932
1992-03-31	9.9431
1992-06-30	9.5903
1992-09-30	9.4551
1992-12-31	6.8044
1993-03-31	5.5159
1993-06-30	5.2634
1993-09-30	5.1289
1993-12-31	4.9511
1994-03-31	4.8305
1994-06-30	4.8615
1994-09-30	5.2903
1994-12-31	5.6646
1995-03-31	6.0585
1995-06-30	6.296
1995-09-30	6.572
1995-12-31	6.3898
1996-03-31	5.94
1996-06-30	5.7408
1996-09-30	5.5247
1996-12-31	5.9016
1997-03-31	5.9225
1997-06-30	6.1972
1997-09-30	6.7682
1997-12-31	7.0307
1998-03-31	6.8869
1998-06-30	7.0938
1998-09-30	7.1269
1998-12-31	6.1803
1999-03-31	5.0793
1999-06-30	4.8663
1999-09-30	4.9148
1999-12-31	5.3117
2000-03-31	5.809
2000-06-30	5.903
2000-09-30	5.808
2000-12-31	5.6847
2001-03-31	5.3782
2001-06-30	5.0238
2001-09-30	4.7183
2001-12-31	3.9111
2002-03-31	3.8847
2002-06-30	3.9651
2002-09-30	3.7953
2002-12-31	3.795
2003-03-31	3.6063
2003-06-30	3.4529
2003-09-30	3.4041
2003-12-31	3.7598
2004-03-31	3.9932
2004-06-30	4.3545
2004-09-30	4.6834
2004-12-31	4.6717
2005-03-31	4.7089
2005-06-30	4.658
2005-09-30	4.4219
2005-12-31	4.4169
2006-03-31	4.3904
2006-06-30	4.4916
2006-09-30	4.7117
2006-12-31	5.0072
2007-03-31	5.3239
2007-06-30	5.5516
2007-09-30	5.7559
2007-12-31	5.4716
2008-03-31	5.0164
2008-06-30	4.962
2008-09-30	4.939
2008-12-31	2.3437
2009-03-31	0.7385
2009-06-30	0.5576
2009-09-30	0.3985
2009-12-31	0.4115
2010-03-31	0.4947
2010-06-30	0.4975
2010-09-30	0.4965
2010-12-31	0.4966
2011-03-31	0.536
2011-06-30	0.5356
2011-09-30	0.4719
2011-12-31	0.392
2012-03-31	0.3834
2012-06-30	0.3726
2012-09-30	0.259
2012-12-31	0.2357
2013-03-31	0.3041
2013-06-30	0.3183
2013-09-30	0.2932
2013-12-31	0.2853
2014-03-31	0.3544
2014-06-30	0.333
2014-09-30	0.4206
2014-12-31	0.4056
2015-03-31	0.3815
2015-06-30	0.45
2015-09-30	0.4706
2015-12-31	0.474
2016-03-31	0.4655
2016-06-30	0.4279
2016-09-30	0.2585
2016-12-31	0.1152
2017-03-31	0.088
2017-06-30	0.0691