Quarter	Percent
1978-04-01	52.7049370250539
1978-07-01	53.3845535390166
1978-10-01	54.3373261900462
1979-01-01	54.9305754621131
1979-04-01	55.0870344599801
1979-07-01	55.1506021967279
1979-10-01	55.3298702623089
1980-01-01	55.5356031085666
1980-04-01	54.8997760711149
1980-07-01	54.6269628782639
1980-10-01	55.4225815010640
1981-01-01	56.3241619672101
1981-04-01	56.4642051717104
1981-07-01	55.5207239794239
1981-10-01	56.1073265373546
1982-01-01	56.9729683334306
1982-04-01	57.7396276994246
1982-07-01	58.1729554362952
1982-10-01	57.5419249477639
1983-01-01	57.9839768174778
1983-04-01	58.5852299089792
1983-07-01	58.4919495594720
1983-10-01	58.7886148277548
1984-01-01	58.5602486301274
1984-04-01	58.5280486380664
1984-07-01	58.9456408838175
1984-10-01	59.0116145841510
1985-01-01	59.5194328558926
1985-04-01	60.0196199445959
1985-07-01	59.3669979318449
1985-10-01	58.4337655741096
1986-01-01	58.6953576623047
1986-04-01	58.0804588435034
1986-07-01	58.6528454902325
1986-10-01	58.0233402073811
1987-01-01	58.0757164247437
1987-04-01	57.8637143748089
1987-07-01	58.5464837611184
1987-10-01	58.3002048598932
1988-01-01	58.0139857899578
1988-04-01	57.4993197393992
1988-07-01	57.7646742713711
1988-10-01	57.6792269851656
1989-01-01	57.3035945540741
1989-04-01	56.5903169201660
1989-07-01	56.7014019123562
1989-10-01	56.6942919053044
1990-01-01	57.7221272663363
1990-04-01	56.4749442430263
1990-07-01	55.2060137703186
1990-10-01	54.9948993838431
1991-01-01	56.1922244592250
1991-04-01	56.2106519850294
1991-07-01	56.9084412920308
1991-10-01	56.2247409218355
1992-01-01	56.5822473958742
1992-04-01	56.4642595230934
1992-07-01	56.1890288631131
1992-10-01	56.8712976527932
1993-01-01	57.2766943014956
1993-04-01	57.0434611044210
1993-07-01	56.6710501790384
1993-10-01	55.6586396100191
1994-01-01	55.6329699406237
1994-04-01	55.1560189216775
1994-07-01	55.3679947312776
1994-10-01	55.4065773394609
1995-01-01	55.7402102780051
1995-04-01	54.9430299784248
1995-07-01	54.8617845931415
1995-10-01	54.2818265996263
1996-01-01	54.4506953291547
1996-04-01	54.2570326264820
1996-07-01	54.0516842634271
1996-10-01	54.2240591075745
1997-01-01	54.2199498014916
1997-04-01	54.1545285478165
1997-07-01	54.1891934017143
1997-10-01	54.1695458707424
1998-01-01	54.5116258907545
1998-04-01	53.0715660371929
1998-07-01	52.7743246612503
1998-10-01	53.4473295520606
1999-01-01	54.3128516316702
1999-04-01	53.8810419241628
1999-07-01	52.9300295143370
1999-10-01	52.5378250574156
2000-01-01	52.7668086020324
2000-04-01	51.5777644356862
2000-07-01	51.0901398485272
2000-10-01	51.6136667117405
2001-01-01	52.2988678418884
2001-04-01	50.7423991447656
2001-07-01	50.8609425725088
2001-10-01	50.2609608344530
2002-01-01	49.7975589461140
2002-04-01	49.2668030401799
2002-07-01	49.6029864708295
2002-10-01	48.7619806116159
2003-01-01	48.3140833550839
2003-04-01	47.5726920217938
2003-07-01	47.5621027661404
2003-10-01	47.5388613522772
2004-01-01	47.8667638431165
2004-04-01	46.3084334976733
2004-07-01	45.6192932212287
2004-10-01	45.8051211441618
2005-01-01	45.8655041883467
2005-04-01	44.7512270335362
2005-07-01	44.1880948515303
2005-10-01	43.8535657226312
2006-01-01	43.8208852682703
2006-04-01	42.8030177452942
2006-07-01	41.9865567105568
2006-10-01	42.3359593956252
2007-01-01	42.5681215028178
2007-04-01	41.5245314600351
2007-07-01	41.6048270073304
2007-10-01	41.9159129102973
2008-01-01	42.5174116269093
2008-04-01	40.9803552875143
2008-07-01	40.4772367146573
2008-10-01	40.6360070201065
2009-01-01	39.6142574249620
2009-04-01	38.8718645597883
2009-07-01	39.0087023830872
2009-10-01	38.2851584943567
2010-01-01	38.1521079449516
2010-04-01	37.6380998094256
2010-07-01	36.9923618690744
2010-10-01	36.6568120223778
2011-01-01	37.2087808592550
2011-04-01	36.6415268344188
2011-07-01	36.3495192694751
2011-10-01	36.7480088030340
2012-01-01	37.1667368136651
2012-04-01	36.2720527511714
2012-07-01	35.9913113653496
2012-10-01	36.0611976552888
2013-01-01	36.3850302796058
2013-04-01	35.6288325851631
2013-07-01	36.1316050429688
2013-10-01	36.4894113645605
2014-01-01	36.6554359870720
2014-04-01	35.8281758637459
2014-07-01	35.4254551089190
2014-10-01	35.9455499699667
2015-01-01	36.0212663830639
2015-04-01	35.1226115740674
2015-07-01	35.1877437281372
2015-10-01	34.1810476865566
2016-01-01	34.3573781481352
2016-04-01	34.4285718318698
2016-07-01	35.3486993633279
2016-10-01	34.8999117901982
2017-01-01	34.8031158627185
2017-04-01	33.4331835274485
2017-07-01	33.4512083621430
2017-10-01	33.1863436268548
2018-01-01	33.6217711718278
2018-04-01	33.4874844814359
2018-07-01	33.1223563038440