Quarter	Percent
1981-03-31	15.4602
1981-06-30	17.8084
1981-09-30	18.5068
1981-12-31	14.4932
1982-03-31	15.1657
1982-06-30	15.1947
1982-09-30	12.6962
1982-12-31	10.0156
1983-03-31	9.2946
1983-06-30	9.4703
1983-09-30	10.201
1983-12-31	9.9752
1984-03-31	10.2168
1984-06-30	11.5278
1984-09-30	11.9366
1984-12-31	9.8985
1985-03-31	9.0219
1985-06-30	8.25
1985-09-30	8.1356
1985-12-31	8.1455
1986-03-31	7.914
1986-06-30	6.9852
1986-09-30	6.2915
1986-12-31	6.1408
1987-03-31	6.3781
1987-06-30	7.1589
1987-09-30	7.2261
1987-12-31	7.966
1988-03-31	6.9621
1988-06-30	7.4868
1988-09-30	8.406
1988-12-31	9.0171
1989-03-31	9.8259
1989-06-30	9.7521
1989-09-30	8.9209
1989-12-31	8.6181
1990-03-31	8.4014
1990-06-30	8.457
1990-09-30	8.166
1990-12-31	8.0938
1991-03-31	6.8821
1991-06-30	6.1645
1991-09-30	5.851
1991-12-31	5.0635
1992-03-31	4.251
1992-06-30	4.0379
1992-09-30	3.4106
1992-12-31	3.6172
1993-03-31	3.2768
1993-06-30	3.2705
1993-09-30	3.2596
1993-12-31	3.4189
1994-03-31	3.5823
1994-06-30	4.4846
1994-09-30	4.9663
1994-12-31	5.9494
1995-03-31	6.2989
1995-06-30	6.1148
1995-09-30	5.8757
1995-12-31	5.8492
1996-03-31	5.4003
1996-06-30	5.5059
1996-09-30	5.5791
1996-12-31	5.5377
1997-03-31	5.5639
1997-06-30	5.7932
1997-09-30	5.6935
1997-12-31	5.8109
1998-03-31	5.6519
1998-06-30	5.6605
1998-09-30	5.582
1998-12-31	5.267
1999-03-31	4.9854
1999-06-30	5.0462
1999-09-30	5.4452
1999-12-31	6.1471
2000-03-31	6.1131
2000-06-30	6.6543
2000-09-30	6.7097
2000-12-31	6.6843
2001-03-31	5.3423
2001-06-30	4.1603
2001-09-30	3.4602
2001-12-31	2.1553
2002-03-31	1.9068
2002-06-30	1.9231
2002-09-30	1.8194
2002-12-31	1.5747
2003-03-31	1.3289
2003-06-30	1.2307
2003-09-30	1.1317
2003-12-31	1.1659
2004-03-31	1.1131
2004-06-30	1.3049
2004-09-30	1.7662
2004-12-31	2.3084
2005-03-31	2.8455
2005-06-30	3.2904
2005-09-30	3.7848
2005-12-31	4.3459
2006-03-31	4.7795
2006-06-30	5.2274
2006-09-30	5.4288
2006-12-31	5.3711
2007-03-31	5.3595
2007-06-30	5.3584
2007-09-30	5.48
2007-12-31	5.0905
2008-03-31	3.3265
2008-06-30	2.9911
2008-09-30	3.302
2008-12-31	3.7003
2009-03-31	1.6837
2009-06-30	1.1918
2009-09-30	0.8077
2009-12-31	0.5317
2010-03-31	0.4968
2010-06-30	0.7643
2010-09-30	0.7002
2010-12-31	0.5261
2011-03-31	0.5038
2011-06-30	0.4558
2011-09-30	0.4877
2011-12-31	0.5452
2012-03-31	0.4875
2012-06-30	0.5403
2012-09-30	0.5358
2012-12-31	0.4291
2013-03-31	0.4658
2013-06-30	0.4331
2013-09-30	0.3574
2013-12-31	0.2994
2014-03-31	0.2929
2014-06-30	0.3062
2014-09-30	0.3654
2014-12-31	0.3698
2015-03-31	0.4462
2015-06-30	0.4233
2015-09-30	0.5052
2015-12-31	0.725
2016-03-31	0.8142
2016-06-30	0.8663
2016-09-30	0.9805
2016-12-31	0.9905
2017-03-31	1.1297
2017-06-30	1.2566
2017-09-30	1.4195
2017-12-31	1.6049
2018-03-31	2.099
2018-06-30	2.4853
2018-09-30	2.4945
2018-12-31	2.7641
2019-03-31	2.8048
2019-06-30	2.6097
2019-09-30	2.2995
2019-12-31	2.0275
2020-03-31	1.6183
2020-06-30	0.652
2020-09-30	0.3143
2020-12-31	0.2895
2021-03-31	0.29
2021-06-30	0.2641