Quarter	Percent
1978-04-01	48.3561457658406
1978-07-01	48.3007903132422
1978-10-01	48.1739487193296
1979-01-01	49.3919151140653
1979-04-01	48.3894590251149
1979-07-01	48.0546554880205
1979-10-01	46.9419977680443
1980-01-01	47.9630156911152
1980-04-01	47.0101236633977
1980-07-01	46.4256544320302
1980-10-01	46.7129894551467
1981-01-01	47.7107807489462
1981-04-01	46.1958723856926
1981-07-01	45.9458316937643
1981-10-01	45.6129578083105
1982-01-01	46.8298803024892
1982-04-01	46.0185611687484
1982-07-01	45.6437108933444
1982-10-01	45.5070985837158
1983-01-01	46.8165186622402
1983-04-01	46.0557990997304
1983-07-01	45.8246665668955
1983-10-01	45.7338613521125
1984-01-01	46.4549414761787
1984-04-01	44.4443705547609
1984-07-01	44.2910036284235
1984-10-01	43.6140788989582
1985-01-01	44.1582427194264
1985-04-01	43.0784893819676
1985-07-01	42.4498707888036
1985-10-01	41.2951552817246
1986-01-01	41.4731035578609
1986-04-01	39.2450946659621
1986-07-01	38.9140077166378
1986-10-01	38.6829752388924
1987-01-01	39.6920045011824
1987-04-01	38.0783871844943
1987-07-01	38.1139526043599
1987-10-01	37.8918125492177
1988-01-01	37.9103112465604
1988-04-01	36.2107597118608
1988-07-01	36.4600942603071
1988-10-01	36.0834876189112
1989-01-01	36.7647011048171
1989-04-01	34.6309341966436
1989-07-01	34.2032017853490
1989-10-01	33.5018644022739
1990-01-01	34.1619695576189
1990-04-01	32.5732484949592
1990-07-01	32.9742402190910
1990-10-01	33.1552791964905
1991-01-01	33.7484490559108
1991-04-01	32.1585188081963
1991-07-01	32.6472358648369
1991-10-01	33.2160944711875
1992-01-01	33.2129855350923
1992-04-01	32.5548540439925
1992-07-01	32.4202777333625
1992-10-01	32.6791017006542
1993-01-01	33.6027165532504
1993-04-01	33.1772823697542
1993-07-01	32.7001482862582
1993-10-01	31.9865651645151
1994-01-01	33.2227799912673
1994-04-01	32.4439658193748
1994-07-01	31.6516937661205
1994-10-01	31.7287949054142
1995-01-01	32.2336467013888
1995-04-01	30.9241451938396
1995-07-01	30.4975425611520
1995-10-01	30.3064731073875
1996-01-01	31.4304892759689
1996-04-01	31.1466990712932
1996-07-01	30.6591953469136
1996-10-01	30.6443360398434
1997-01-01	31.0685679650579
1997-04-01	30.5707388734680
1997-07-01	30.4547133431929
1997-10-01	30.6382188080891
1998-01-01	31.6084709851108
1998-04-01	30.5751426501195
1998-07-01	30.1513068556521
1998-10-01	30.4021452253498
1999-01-01	31.5239395977576
1999-04-01	30.7016822487226
1999-07-01	30.3112125035975
1999-10-01	29.9494425021856
2000-01-01	30.6525296471295
2000-04-01	29.3240713007667
2000-07-01	28.7016954639600
2000-10-01	29.4815669629825
2001-01-01	29.9455553069981
2001-04-01	28.3199029546835
2001-07-01	28.5131735138358
2001-10-01	28.7527240734177
2002-01-01	29.2390850406731
2002-04-01	28.7615461056070
2002-07-01	28.0033223351739
2002-10-01	27.7474303681779
2003-01-01	27.5035477904294
2003-04-01	27.0958329330687
2003-07-01	27.4495268093451
2003-10-01	27.9844347452395
2004-01-01	28.7925299482130
2004-04-01	28.2030061999548
2004-07-01	27.9820645689222
2004-10-01	27.5885887828711
2005-01-01	27.1493472877046
2005-04-01	26.0462062049387
2005-07-01	26.0123049961217
2005-10-01	26.0871780013472
2006-01-01	26.5967146107091
2006-04-01	25.5523478352060
2006-07-01	25.4704258502091
2006-10-01	25.5339132541265
2007-01-01	25.7956878907509
2007-04-01	25.3519377740571
2007-07-01	24.9745170859775
2007-10-01	24.7388647391177
2008-01-01	25.1858223918545
2008-04-01	24.4771833044040
2008-07-01	24.4995543705125
2008-10-01	24.3239426656354
2009-01-01	24.2725050710846
2009-04-01	23.9502412891276
2009-07-01	24.4378288490187
2009-10-01	25.1414546185309
2010-01-01	25.6985870617539
2010-04-01	24.9509538832908
2010-07-01	24.4556713686014
2010-10-01	24.3150978319206
2011-01-01	24.8722577400492
2011-04-01	24.2185883246390
2011-07-01	24.1245641201615
2011-10-01	24.2428915512168
2012-01-01	24.9350543906476
2012-04-01	24.3426083556023
2012-07-01	24.1817352054597
2012-10-01	24.2797963110735
2013-01-01	24.4240804093829
2013-04-01	23.8750789335529
2013-07-01	24.2304589977952
2013-10-01	24.2607578892753
2014-01-01	24.3013675859158
2014-04-01	24.0167110479643
2014-07-01	24.0664921847207
2014-10-01	24.1358053166537
2015-01-01	23.9464584094499
2015-04-01	23.3360613917122
2015-07-01	23.3486621496972
2015-10-01	23.0627436135524
2016-01-01	23.2990983158952
2016-04-01	22.9349887286820
2016-07-01	23.2313698373334
2016-10-01	23.0354835592064
2017-01-01	23.2198255138109
2017-04-01	22.2534543229714
2017-07-01	22.3599882377013
2017-10-01	21.4214801903881
2018-01-01	21.4616098077812
2018-04-01	21.1305540345612
2018-07-01	21.6453562871578