Quarter	Percent
1968-01-01	85.1964422934376
1968-04-01	87.8834295589333
1968-07-01	87.3759124978637
1968-10-01	87.5884509846774
1969-01-01	85.3562433991388
1969-04-01	88.0888888888889
1969-07-01	87.9531388152078
1969-10-01	88.0070546737213
1970-01-01	85.7644771559506
1970-04-01	87.3905235529769
1970-07-01	87.4454909573086
1970-10-01	86.5322200464172
1971-01-01	86.4059661193728
1971-04-01	87.9420440163071
1971-07-01	87.4784671242679
1971-10-01	87.2322193658954
1972-01-01	85.6033179672910
1972-04-01	87.9965457685665
1972-07-01	87.0608397600686
1972-10-01	85.4219948849105
1973-01-01	85.6899281451711
1973-04-01	86.8192353830569
1973-07-01	87.2773536895674
1973-10-01	87.5199061813020
1974-01-01	85.9202714164546
1974-04-01	86.3214242439979
1974-07-01	86.9272645444946
1974-10-01	86.8320610687023
1975-01-01	85.2907537107242
1975-04-01	86.6163167454498
1975-07-01	87.0800264968841
1975-10-01	86.9962744030817
1976-01-01	85.8580706372296
1976-04-01	86.9053884711779
1976-07-01	87.0323651898446
1976-10-01	85.8936820469556
1977-01-01	84.1628686124932
1977-04-01	85.6314849847268
1977-07-01	85.2928297755884
1977-10-01	85.4106905831044
1978-01-01	84.0876617995433
1978-04-01	85.9440748489621
1978-07-01	85.4274526372794
1978-10-01	85.8293606078992
1979-01-01	84.1257918443730
1979-04-01	86.4452251028047
1979-07-01	85.8379286756648
1979-10-01	85.8700478710454
1980-01-01	84.9233462514582
1980-04-01	86.5360173623798
1980-07-01	85.9275850769705
1980-10-01	85.3977426706085
1981-01-01	85.1677327550543
1981-04-01	85.9722778529798
1981-07-01	85.5408279460877
1981-10-01	84.4014772724433
1982-01-01	84.3171669825658
1982-04-01	85.6846498048466
1982-07-01	85.9575185150674
1982-10-01	84.7970544881273
1983-01-01	84.1360864134904
1983-04-01	85.8335459510494
1983-07-01	85.3484268194997
1983-10-01	84.6419765715172
1984-01-01	84.1303934811067
1984-04-01	84.5167478337671
1984-07-01	84.3224028379180
1984-10-01	83.6351073638197
1985-01-01	83.0151465906819
1985-04-01	84.3196098066054
1985-07-01	83.4388777905274
1985-10-01	83.2480314840184
1986-01-01	82.5405310492751
1986-04-01	83.4912198855988
1986-07-01	83.8198390898268
1986-10-01	83.2879891850424
1987-01-01	82.2387649682489
1987-04-01	83.5266003392319
1987-07-01	83.4732318577761
1987-10-01	82.7974876503998
1988-01-01	82.0498418749506
1988-04-01	82.5708012173537
1988-07-01	82.9968849918864
1988-10-01	82.4405050018098
1989-01-01	81.9656421412704
1989-04-01	82.9552671061671
1989-07-01	83.2765144674805
1989-10-01	83.5521461266089
1990-01-01	82.7210661214262
1990-04-01	83.4850042044286
1990-07-01	83.7626340329630
1990-10-01	84.4878616808441
1991-01-01	84.0213819155901
1991-04-01	84.7773155298854
1991-07-01	84.8015189980356
1991-10-01	85.3215029028371
1992-01-01	84.6865361260928
1992-04-01	84.9793481068711
1992-07-01	84.8712126325239
1992-10-01	85.7141969648400
1993-01-01	85.2554246630902
1993-04-01	85.2751950835332
1993-07-01	85.8564408801030
1993-10-01	84.9772874756652
1994-01-01	84.4414292175486
1994-04-01	85.2287291728286
1994-07-01	85.8823471574932
1994-10-01	85.0113009474705
1995-01-01	84.0752509223214
1995-04-01	85.1442093712909
1995-07-01	84.8385362672214
1995-10-01	85.6506238859180
1996-01-01	84.0728319687226
1996-04-01	84.9178230873508
1996-07-01	85.4817612236067
1996-10-01	86.0145030015304
1997-01-01	84.8236722697284
1997-04-01	85.7937759405774
1997-07-01	84.9575772523213
1997-10-01	85.0618864703372
1998-01-01	84.9490177056904
1998-04-01	85.7326851503636
1998-07-01	84.8947331361780
1998-10-01	85.0480643497945
1999-01-01	85.8756049471231
1999-04-01	85.2747298420615
1999-07-01	84.9496660680468
1999-10-01	84.8635235732010
2000-01-01	84.3088772506054
2000-04-01	83.9850021222433
2000-07-01	84.4105131414268
2000-10-01	84.0307106978193
2001-01-01	83.9976870237738
2001-04-01	83.3833083458271
2001-07-01	83.1770401083311
2001-10-01	83.1298132721465
2002-01-01	83.2223437064623
2002-04-01	83.2104928475193
2002-07-01	82.1872808794884
2002-10-01	83.0300423716274
2003-01-01	82.8320534780981
2003-04-01	83.0684473321925
2003-07-01	82.9615253140868
2003-10-01	83.4235928023905
2004-01-01	82.5169720339974
2004-04-01	82.6271767838904
2004-07-01	82.9101978564117
2004-10-01	82.8458321394524
2005-01-01	82.7928388236259
2005-04-01	83.0950159726345
2005-07-01	83.5153900137704
2005-10-01	82.9157777028065
2006-01-01	83.3750073676632
2006-04-01	84.3343079002798
2006-07-01	83.9350008364093
2006-10-01	83.5865111972831
2007-01-01	84.8355825636556
2007-04-01	84.9730856878554
2007-07-01	84.9839074960861
2007-10-01	84.9481037832334
2008-01-01	85.0804202412838
2008-04-01	85.2130325814536
2008-07-01	84.9768703388621
2008-10-01	85.3595677863012
2009-01-01	84.8735535111142
2009-04-01	84.7519237124109
2009-07-01	84.5176704357288
2009-10-01	84.3726246234880
2010-01-01	84.3952304520921
2010-04-01	84.3930203390654
2010-07-01	83.9520951070247
2010-10-01	83.8129328964028
2011-01-01	83.9432349129506
2011-04-01	84.5243232124519
2011-07-01	83.1123107390571
2011-10-01	83.5608237547893
2012-01-01	83.0558029023753
2012-04-01	82.8113303743274
2012-07-01	82.5701496396576
2012-10-01	83.2022949327344
2013-01-01	83.4542797790668
2013-04-01	83.2894739610274
2013-07-01	83.6483558438616
2013-10-01	83.9688233124260
2014-01-01	84.6671999747211
2014-04-01	84.5943902341216
2014-07-01	85.1688165377459
2014-10-01	85.0808716927710
2015-01-01	85.6204539026796
2015-04-01	85.1951358889083
2015-07-01	86.3029728992157
2015-10-01	85.7141725561694
2016-01-01	85.9878490735451
2016-04-01	86.4703769188478
2016-07-01	87.0554214585024
2016-10-01	86.6492029073101
2017-01-01	87.0016989613746
2017-04-01	87.2502790958390
2017-07-01	88.1223424573249
2017-10-01	88.2764654418198
2018-01-01	88.0496793123414
2018-04-01	88.8204827518812
2018-07-01	88.3545907938844