Quarter	Percent
1968-01-01	44.6027665204578
1968-04-01	39.2870763785992
1968-07-01	40.1533823395698
1968-10-01	42.6882756960171
1969-01-01	45.2828671016177
1969-04-01	40.6729270729271
1969-07-01	41.4780163283157
1969-10-01	43.7121390697787
1970-01-01	44.9374595946820
1970-04-01	40.4770585997520
1970-07-01	40.7518022449331
1970-10-01	43.0830970282365
1971-01-01	42.6961698429593
1971-04-01	38.2757196904227
1971-07-01	40.1451790155590
1971-10-01	42.1560656301459
1972-01-01	42.9366481109605
1972-04-01	40.2935275941613
1972-07-01	41.1928317783735
1972-10-01	44.2489628384323
1973-01-01	45.8073393790262
1973-04-01	42.2214991052646
1973-07-01	43.5642515669061
1973-10-01	46.5377228987474
1974-01-01	47.6266014662326
1974-04-01	44.6302708765091
1974-07-01	46.8004547102704
1974-10-01	48.8484470846264
1975-01-01	51.2592384853562
1975-04-01	48.7096788547882
1975-07-01	49.5361892761655
1975-10-01	49.5313803785203
1976-01-01	51.2393010528150
1976-04-01	50.5735839558039
1976-07-01	51.2326211898552
1976-10-01	53.4713855709691
1977-01-01	54.5417556069667
1977-04-01	53.2334510150044
1977-07-01	53.0057039303645
1977-10-01	55.3474890060256
1978-01-01	55.9748770073841
1978-04-01	52.2270840851678
1978-07-01	55.2015154917380
1978-10-01	56.6339637394354
1979-01-01	58.0565805658056
1979-04-01	53.8057410450048
1979-07-01	55.4452049306372
1979-10-01	57.0900571445735
1980-01-01	59.0190169665088
1980-04-01	55.6471247935364
1980-07-01	56.1356789210042
1980-10-01	57.2411003236246
1981-01-01	58.3250976150244
1981-04-01	54.6078279725411
1981-07-01	55.7108474899886
1981-10-01	57.6338915602719
1982-01-01	58.9894050529747
1982-04-01	54.6733286332382
1982-07-01	56.2053585472750
1982-10-01	56.5586594271188
1983-01-01	57.4636645379421
1983-04-01	53.6501775956223
1983-07-01	55.7652687612609
1983-10-01	56.7768564212546
1984-01-01	58.3599430831457
1984-04-01	54.7803227737269
1984-07-01	56.0916000765265
1984-10-01	57.0487778557168
1985-01-01	59.0184416304025
1985-04-01	55.9139996984972
1985-07-01	56.6938918466110
1985-10-01	57.6949664160803
1986-01-01	59.1782664657424
1986-04-01	55.4636225446547
1986-07-01	56.4270008018153
1986-10-01	57.7289972899729
1987-01-01	59.7804073262856
1987-04-01	55.8808089965834
1987-07-01	56.5648818916929
1987-10-01	58.1378325809911
1988-01-01	60.4332006512706
1988-04-01	55.4007422162311
1988-07-01	57.1502383372249
1988-10-01	58.1043980239370
1989-01-01	59.9593144236358
1989-04-01	55.6294902898398
1989-07-01	56.8674681707525
1989-10-01	57.4047503120292
1990-01-01	59.2036539133532
1990-04-01	54.6745538879750
1990-07-01	55.5849103898660
1990-10-01	55.8729392258583
1991-01-01	57.5625666689223
1991-04-01	53.1130119374697
1991-07-01	53.2733825481882
1991-10-01	54.6922300706357
1992-01-01	55.6788004728084
1992-04-01	52.2239246290518
1992-07-01	52.0209167103461
1992-10-01	52.9193873659470
1993-01-01	54.9237153195614
1993-04-01	51.3974096796183
1993-07-01	51.4845895486909
1993-10-01	51.5380411937789
1994-01-01	54.2079376382791
1994-04-01	50.3784325097300
1994-07-01	50.7766659979459
1994-10-01	52.1440619812204
1995-01-01	54.0011207606544
1995-04-01	50.9596782908211
1995-07-01	50.6323553879430
1995-10-01	52.0601815902043
1996-01-01	52.8906746377188
1996-04-01	49.6430348241561
1996-07-01	49.9464883383284
1996-10-01	51.4447650785169
1997-01-01	52.2488440521227
1997-04-01	49.0629243755059
1997-07-01	49.3887009303963
1997-10-01	51.4153551497157
1998-01-01	53.3051800373686
1998-04-01	49.7347225099642
1998-07-01	50.1529475884067
1998-10-01	51.1134538236601
1999-01-01	53.5788860509925
1999-04-01	50.4076296310981
1999-07-01	51.7116494396185
1999-10-01	52.9499737598030
2000-01-01	54.4899952620827
2000-04-01	50.6604130272889
2000-07-01	52.3898822729875
2000-10-01	52.7236882330810
2001-01-01	55.3547716848345
2001-04-01	51.1958627888259
2001-07-01	52.7068786367415
2001-10-01	54.3285891283703
2002-01-01	55.5772143288026
2002-04-01	52.5274118541953
2002-07-01	52.3504897856894
2002-10-01	55.2220486918401
2003-01-01	55.9002439593361
2003-04-01	52.9572927806486
2003-07-01	54.4455066690217
2003-10-01	55.5860222238448
2004-01-01	58.0044969218760
2004-04-01	54.8101919294684
2004-07-01	54.6725660100584
2004-10-01	55.6264146778865
2005-01-01	58.6520027185832
2005-04-01	54.9814340910231
2005-07-01	54.2185500047760
2005-10-01	54.2595386109804
2006-01-01	56.9224879693784
2006-04-01	54.1199871431741
2006-07-01	54.5917678610497
2006-10-01	55.7776661549058
2007-01-01	57.0525627744068
2007-04-01	52.4905627370661
2007-07-01	54.7951432177192
2007-10-01	55.6871278466043
2008-01-01	58.6720902674958
2008-04-01	53.4244677842802
2008-07-01	54.5540506829349
2008-10-01	56.0901593591044
2009-01-01	59.0136145619209
2009-04-01	55.2173934897278
2009-07-01	56.7839230224064
2009-10-01	58.7182408582930
2010-01-01	59.7138467865285
2010-04-01	56.5594691168964
2010-07-01	57.3561743585823
2010-10-01	58.3861095640520
2011-01-01	60.4478771884570
2011-04-01	55.2771568296681
2011-07-01	57.3849431153144
2011-10-01	58.9286039560512
2012-01-01	60.6106990447205
2012-04-01	56.9694644493036
2012-07-01	57.5136599663494
2012-10-01	58.9295177530472
2013-01-01	60.2129586292505
2013-04-01	56.5333333333333
2013-07-01	57.2938774837167
2013-10-01	59.2196738966402
2014-01-01	59.7744723092460
2014-04-01	56.3772775991426
2014-07-01	56.6049618464973
2014-10-01	58.5614600107354
2015-01-01	59.5596765535990
2015-04-01	56.9282115214794
2015-07-01	57.1508092495849
2015-10-01	56.7287661397359
2016-01-01	58.3060361956988
2016-04-01	53.7190877132710
2016-07-01	55.4602261796796
2016-10-01	55.0747863247863
2017-01-01	58.1691303483804
2017-04-01	53.5850458998297
2017-07-01	54.9900683910070
2017-10-01	56.2335659001077
2018-01-01	56.1040339702760
2018-04-01	51.5627401429583
2018-07-01	52.3328471006490