Quarter	Percent
1978-01-01	81.5465471524548
1978-04-01	83.0083310616446
1978-07-01	82.4647347021290
1978-10-01	82.0900403501422
1979-01-01	81.2451963052729
1979-04-01	82.8598726991642
1979-07-01	82.5336965037408
1979-10-01	81.9665216713926
1980-01-01	80.9480462734108
1980-04-01	82.3883089438876
1980-07-01	82.1960647037640
1980-10-01	81.9115710136882
1981-01-01	81.4817338291505
1981-04-01	82.5385093832515
1981-07-01	82.0944467278066
1981-10-01	81.3861705630996
1982-01-01	80.8946076265870
1982-04-01	82.4046511895583
1982-07-01	81.7730020688880
1982-10-01	81.6114911137813
1983-01-01	81.1584497786166
1983-04-01	82.4449148834012
1983-07-01	81.9618760022680
1983-10-01	81.3249914887150
1984-01-01	80.5204826144758
1984-04-01	81.7556580572572
1984-07-01	81.4292961728014
1984-10-01	80.9293543610581
1985-01-01	80.0362412453326
1985-04-01	81.1033680867737
1985-07-01	80.7403654548047
1985-10-01	80.3302996021177
1986-01-01	79.5300352592955
1986-04-01	80.6653744403386
1986-07-01	80.7015979013475
1986-10-01	79.9468408791062
1987-01-01	79.1611736358458
1987-04-01	80.4467808450566
1987-07-01	80.4027913902864
1987-10-01	79.7029670207714
1988-01-01	78.9193129376440
1988-04-01	80.3874768906386
1988-07-01	80.0990686070674
1988-10-01	79.5674731758454
1989-01-01	78.7005925423184
1989-04-01	80.2517723174544
1989-07-01	80.1079008772088
1989-10-01	79.7268484981806
1990-01-01	78.9234641897579
1990-04-01	80.4069286689648
1990-07-01	80.2840232107897
1990-10-01	80.2380644777366
1991-01-01	79.6038294427174
1991-04-01	80.8636215815703
1991-07-01	80.8871322474519
1991-10-01	80.5035826953273
1992-01-01	80.2637813816216
1992-04-01	81.1283194964500
1992-07-01	81.1335159315646
1992-10-01	81.1310136446628
1993-01-01	80.2686128914057
1993-04-01	81.3719976729570
1993-07-01	81.3315659135134
1993-10-01	81.2241980149753
1994-01-01	80.2060315512792
1994-04-01	81.2848396103852
1994-07-01	81.3405770085951
1994-10-01	80.7327101134131
1995-01-01	79.8925337513318
1995-04-01	80.9650102069226
1995-07-01	81.4336803793970
1995-10-01	80.8404054964835
1996-01-01	80.0233627176320
1996-04-01	81.3281278302081
1996-07-01	81.5504486912333
1996-10-01	81.0349696461946
1997-01-01	80.5891149109670
1997-04-01	81.6746252838479
1997-07-01	81.2594891987152
1997-10-01	80.7741881826559
1998-01-01	80.1623463720946
1998-04-01	81.2130896797687
1998-07-01	80.9305425915423
1998-10-01	80.5865341080437
1999-01-01	80.0134684637042
1999-04-01	80.7917428266105
1999-07-01	80.6721321033243
1999-10-01	80.4384684099024
2000-01-01	79.6437825967118
2000-04-01	80.3765003275354
2000-07-01	80.2860247926322
2000-10-01	80.3977130449372
2001-01-01	79.3831910867490
2001-04-01	80.1093191429159
2001-07-01	79.8880427261224
2001-10-01	79.4418890615027
2002-01-01	78.7225386365168
2002-04-01	79.2891433770059
2002-07-01	79.4138664583147
2002-10-01	78.8752342518269
2003-01-01	78.2121477620856
2003-04-01	79.1922149638777
2003-07-01	78.8313246629161
2003-10-01	78.5703685735863
2004-01-01	77.6829014894647
2004-04-01	78.6018866916603
2004-07-01	78.5259290758272
2004-10-01	78.2227949864191
2005-01-01	77.6516572519502
2005-04-01	78.5149638912395
2005-07-01	78.6603733528642
2005-10-01	78.5026794550075
2006-01-01	77.9573096748042
2006-04-01	78.9124041196396
2006-07-01	78.8139790327067
2006-10-01	78.5156296226033
2007-01-01	78.2596271356305
2007-04-01	79.3415030261011
2007-07-01	78.9949337387242
2007-10-01	78.7088286779641
2008-01-01	78.3316749548144
2008-04-01	79.2313908643906
2008-07-01	78.8543711499270
2008-10-01	78.6795096750941
2009-01-01	78.0836063266611
2009-04-01	78.7198681332051
2009-07-01	78.3152618229361
2009-10-01	77.9344167722554
2010-01-01	77.8156149637213
2010-04-01	78.5024738531628
2010-07-01	78.2950171923484
2010-10-01	77.9431501331303
2011-01-01	77.7749284594272
2011-04-01	78.3925757103329
2011-07-01	77.7970728130600
2011-10-01	77.7505464558534
2012-01-01	77.4236289628892
2012-04-01	77.9273548610797
2012-07-01	77.7498779382019
2012-10-01	77.6053406972611
2013-01-01	77.3757986578695
2013-04-01	78.1170996733852
2013-07-01	77.9754925257403
2013-10-01	77.6765061125916
2014-01-01	77.4620885417952
2014-04-01	78.2156472017719
2014-07-01	78.1032629895684
2014-10-01	77.6426397952533
2015-01-01	77.7652543378724
2015-04-01	78.0394950083562
2015-07-01	78.2025453497984
2015-10-01	78.1236379232949
2016-01-01	77.8539307048031
2016-04-01	78.6519243036360
2016-07-01	78.6577183455278
2016-10-01	78.8195094114942
2017-01-01	78.1747332985699
2017-04-01	78.8967425926257
2017-07-01	79.0459251247686
2017-10-01	78.8650644675384
2018-01-01	78.9609689695958
2018-04-01	79.9455837874898
2018-07-01	79.8396094461278