Quarter	Percent
1968-01-01	49.0898993388481
1968-04-01	43.5607808508496
1968-07-01	44.4057946804381
1968-10-01	46.4746870880047
1969-01-01	49.2776961949571
1969-04-01	44.3748138269561
1969-07-01	44.9990438353946
1969-10-01	46.9129821670465
1970-01-01	49.2853952536803
1970-04-01	44.5433397956806
1970-07-01	45.1049905105406
1970-10-01	47.2383306705866
1971-01-01	49.3832632842665
1971-04-01	45.8467472836132
1971-07-01	46.4981067844887
1971-10-01	48.1334120609048
1972-01-01	50.4962566315008
1972-04-01	47.5256076197893
1972-07-01	47.5148625482946
1972-10-01	47.8802809407138
1973-01-01	49.2342236847916
1973-04-01	47.0936844297162
1973-07-01	47.2048214034845
1973-10-01	47.7728392416518
1974-01-01	50.9668465679494
1974-04-01	47.9266206833366
1974-07-01	48.8400049783417
1974-10-01	49.9517283509333
1975-01-01	52.4312606626180
1975-04-01	48.7776028520201
1975-07-01	48.8134791777621
1975-10-01	50.4898565172796
1976-01-01	52.0880567445716
1976-04-01	49.1530545750153
1976-07-01	48.6189061597475
1976-10-01	49.9482112794917
1977-01-01	51.5274458107910
1977-04-01	47.4655745996937
1977-07-01	47.6755925530786
1977-10-01	48.6558277617415
1978-01-01	50.4745047986788
1978-04-01	46.5003837218462
1978-07-01	46.9741021130137
1978-10-01	47.8117559823482
1979-01-01	49.5670303630325
1979-04-01	46.3300308646132
1979-07-01	46.5040688804888
1979-10-01	47.4908028487861
1980-01-01	49.6752709729271
1980-04-01	46.1018941503447
1980-07-01	45.9825105648770
1980-10-01	47.4164191060036
1981-01-01	49.5398259705489
1981-04-01	45.8978840038464
1981-07-01	46.2822679215584
1981-10-01	46.6185361291687
1982-01-01	48.3876755492139
1982-04-01	45.5350420528614
1982-07-01	46.1065837921431
1982-10-01	46.1419768657915
1983-01-01	47.0906282870969
1983-04-01	44.2084112576395
1983-07-01	44.4280305140247
1983-10-01	45.5133745446090
1984-01-01	47.4974643172783
1984-04-01	44.1895238004801
1984-07-01	44.2481034102430
1984-10-01	45.0789135814228
1985-01-01	46.8264469041106
1985-04-01	44.1469184808520
1985-07-01	44.3708143821596
1985-10-01	45.4493612493956
1986-01-01	46.5540586766558
1986-04-01	43.9983517570404
1986-07-01	44.2140418192372
1986-10-01	45.3201885256649
1987-01-01	46.7180255375101
1987-04-01	43.6491202595449
1987-07-01	44.2347287962596
1987-10-01	44.7965099190586
1988-01-01	46.0415255365248
1988-04-01	43.2451266871559
1988-07-01	43.7517272591170
1988-10-01	44.6127278637270
1989-01-01	45.3486076677424
1989-04-01	42.3263290152724
1989-07-01	42.9619678010930
1989-10-01	43.4528339021039
1990-01-01	44.1879107670291
1990-04-01	41.6181589515569
1990-07-01	42.1342756020964
1990-10-01	42.6185093378691
1991-01-01	43.4665256746084
1991-04-01	40.8997015252638
1991-07-01	41.2671398173693
1991-10-01	41.5615241277702
1992-01-01	42.9412496389126
1992-04-01	40.6988415972055
1992-07-01	41.3687082704869
1992-10-01	41.2244682450177
1993-01-01	43.2970288777091
1993-04-01	40.7495460994445
1993-07-01	41.3444022366340
1993-10-01	41.4205302696518
1994-01-01	42.8845536324393
1994-04-01	40.2881328647359
1994-07-01	41.4003778250093
1994-10-01	41.8201091292340
1995-01-01	42.6303982769466
1995-04-01	40.5265904571410
1995-07-01	41.0859135369449
1995-10-01	41.7636776119174
1996-01-01	42.4506677229069
1996-04-01	40.1390304918610
1996-07-01	40.3762142163271
1996-10-01	41.2476868770701
1997-01-01	41.6189164370801
1997-04-01	39.5874392900277
1997-07-01	39.6609016471654
1997-10-01	40.3534749980900
1998-01-01	41.0906542126239
1998-04-01	39.4108400768175
1998-07-01	39.6607443569197
1998-10-01	40.5742719053001
1999-01-01	41.4960102939749
1999-04-01	39.5548589309922
1999-07-01	39.8517088339497
1999-10-01	40.6660444905020
2000-01-01	41.6471645143809
2000-04-01	39.5480390761434
2000-07-01	40.0247665913931
2000-10-01	40.1456013320786
2001-01-01	40.5045310513106
2001-04-01	39.4192760450699
2001-07-01	39.8756487164445
2001-10-01	39.8963192447339
2002-01-01	40.9680652132736
2002-04-01	39.9143042450545
2002-07-01	39.8593848707864
2002-10-01	39.9536604884213
2003-01-01	41.0056652505953
2003-04-01	39.3964539153824
2003-07-01	39.6548860554945
2003-10-01	39.8795003981286
2004-01-01	40.6290527879174
2004-04-01	39.4009580925148
2004-07-01	39.0464928953136
2004-10-01	39.8760430694272
2005-01-01	40.2716546303172
2005-04-01	38.4538522327941
2005-07-01	38.5023850938176
2005-10-01	39.2769754263763
2006-01-01	39.7580775338405
2006-04-01	38.0381326600004
2006-07-01	38.1377915485353
2006-10-01	38.4762734469110
2007-01-01	39.2162562001002
2007-04-01	37.2221925454869
2007-07-01	37.8520157748750
2007-10-01	37.6312602771905
2008-01-01	38.5624085506555
2008-04-01	36.8933718740482
2008-07-01	37.4410157119399
2008-10-01	37.4154091191897
2009-01-01	37.8148909413115
2009-04-01	36.6549027472961
2009-07-01	36.3738166572252
2009-10-01	36.8192708717806
2010-01-01	37.5339620651127
2010-04-01	36.5014859553560
2010-07-01	36.2321354798472
2010-10-01	36.5315141554082
2011-01-01	36.8812897000512
2011-04-01	35.5201942354627
2011-07-01	36.1819770906817
2011-10-01	36.6716071604438
2012-01-01	37.4852408631275
2012-04-01	36.0986015473300
2012-07-01	36.3674765702393
2012-10-01	36.2715736645365
2013-01-01	35.9506817573225
2013-04-01	34.7500153139426
2013-07-01	34.8983105121312
2013-10-01	34.1479468556151
2014-01-01	34.9651120654685
2014-04-01	33.7454721739266
2014-07-01	33.6749968533664
2014-10-01	33.2527137977514
2015-01-01	34.0367542801996
2015-04-01	33.0055006045306
2015-07-01	32.6960994032210
2015-10-01	32.6105332076271
2016-01-01	32.6750742459339
2016-04-01	31.9661726462461
2016-07-01	31.2812941951385
2016-10-01	31.3250297440828
2017-01-01	31.7556485142002
2017-04-01	30.4389946853772
2017-07-01	30.0487463138185
2017-10-01	29.9626177856291
2018-01-01	29.5312352987695
2018-04-01	28.6505353956358
2018-07-01	28.1277404569358