Quarter	Percent
1968-01-01	33.1564701190524
1968-04-01	29.2683304578782
1968-07-01	29.7176503440445
1968-10-01	31.1586673226913
1969-01-01	33.2583667374404
1969-04-01	29.7044642650224
1969-07-01	30.1270549921356
1969-10-01	31.5152367236209
1970-01-01	33.0674618911196
1970-04-01	29.8227860600517
1970-07-01	30.1752269139768
1970-10-01	31.5660345607236
1971-01-01	32.6463504632835
1971-04-01	30.1013005002538
1971-07-01	30.7608047886718
1971-10-01	31.7774110856321
1972-01-01	33.1231656184382
1972-04-01	30.9446630369365
1972-07-01	31.0081662258773
1972-10-01	31.6896505146177
1973-01-01	32.4826362618361
1973-04-01	30.6943537479553
1973-07-01	30.8287817877744
1973-10-01	31.4167223585761
1974-01-01	33.2649348193887
1974-04-01	31.1360395634057
1974-07-01	31.8288455157394
1974-10-01	32.5378761629235
1975-01-01	34.2507277001346
1975-04-01	31.8851699453639
1975-07-01	31.8954583794920
1975-10-01	32.6035767394652
1976-01-01	33.7992830614649
1976-04-01	32.0149477124114
1976-07-01	31.7949308901010
1976-10-01	32.6266119502396
1977-01-01	33.7840916040988
1977-04-01	31.3566789404114
1977-07-01	31.4906219376714
1977-10-01	32.1552279009832
1978-01-01	33.2843266502152
1978-04-01	30.6464347157198
1978-07-01	31.2390345044691
1978-10-01	31.7872448174169
1979-01-01	32.9937784751493
1979-04-01	30.6008084651691
1979-07-01	30.8227382987173
1979-10-01	31.5474668749621
1980-01-01	33.0559680665859
1980-04-01	30.7011870820190
1980-07-01	30.6931886574546
1980-10-01	31.5551402037118
1981-01-01	32.7553289531593
1981-04-01	30.4328444244253
1981-07-01	30.8330006957871
1981-10-01	31.3181265843634
1982-01-01	32.2969515490913
1982-04-01	30.2203596484056
1982-07-01	30.7944530242112
1982-10-01	30.8822476974498
1983-01-01	31.5453090362903
1983-04-01	29.5168047742812
1983-07-01	29.8714464969447
1983-10-01	30.6558728959367
1984-01-01	31.9284365581509
1984-04-01	29.7869974237155
1984-07-01	29.9499694892621
1984-10-01	30.5742994398428
1985-01-01	31.8317284377894
1985-04-01	29.9931446607581
1985-07-01	30.2971314270598
1985-10-01	31.0369169244408
1986-01-01	31.8721439574425
1986-04-01	30.0538093454656
1986-07-01	30.1755557337445
1986-10-01	31.0884861806831
1987-01-01	32.1280388608238
1987-04-01	30.0328314762281
1987-07-01	30.3114402471809
1987-10-01	30.9211841835912
1988-01-01	31.9003941352760
1988-04-01	29.8904595480478
1988-07-01	30.2433355078602
1988-10-01	30.9191641917613
1989-01-01	31.5692010751446
1989-04-01	29.3928734533945
1989-07-01	29.8466548135359
1989-10-01	30.2448525497139
1990-01-01	30.8734320012498
1990-04-01	28.9558155903338
1990-07-01	29.3133190237949
1990-10-01	29.5076986286151
1991-01-01	30.1992590317178
1991-04-01	28.3475254930315
1991-07-01	28.6215939032112
1991-10-01	28.8027864681961
1992-01-01	29.6327327818778
1992-04-01	28.1199739332811
1992-07-01	28.4993042205661
1992-10-01	28.3560918258797
1993-01-01	29.7484610925304
1993-04-01	27.9758560416467
1993-07-01	28.2653592316480
1993-10-01	28.3259258176341
1994-01-01	29.5247964204749
1994-04-01	27.6968354426480
1994-07-01	28.1993337601745
1994-10-01	28.6481864612173
1995-01-01	29.4348928713332
1995-04-01	27.8394784892429
1995-07-01	27.9465882630106
1995-10-01	28.4274876334211
1996-01-01	29.0704698733226
1996-04-01	27.3326256530038
1996-07-01	27.3306350037619
1996-10-01	27.9560826291606
1997-01-01	28.2496817148321
1997-04-01	26.7522777973382
1997-07-01	26.9242349778655
1997-10-01	27.5094191839867
1998-01-01	28.0694736804890
1998-04-01	26.7468928879402
1998-07-01	26.9791755665001
1998-10-01	27.5236456010160
1999-01-01	28.1757116534136
1999-04-01	26.8740903152189
1999-07-01	27.1058975524881
1999-10-01	27.5837532266598
2000-01-01	28.3605563681633
2000-04-01	26.9204312120360
2000-07-01	27.1994142442775
2000-10-01	27.2594175281873
2001-01-01	27.8215693415755
2001-04-01	26.8834144573615
2001-07-01	27.2220202147431
2001-10-01	27.4521691658368
2002-01-01	28.2127855227838
2002-04-01	27.3717917048846
2002-07-01	27.3271717462619
2002-10-01	27.5671187246310
2003-01-01	28.2678206833616
2003-04-01	27.1510801554437
2003-07-01	27.3618797705069
2003-10-01	27.4957920748935
2004-01-01	28.2933694688440
2004-04-01	27.3574596946759
2004-07-01	27.1674687298132
2004-10-01	27.6581839784967
2005-01-01	28.1511270838594
2005-04-01	26.8868337317824
2005-07-01	26.7937694289743
2005-10-01	27.2271211650643
2006-01-01	27.6120711475098
2006-04-01	26.3620554871580
2006-07-01	26.5309956613203
2006-10-01	26.7715291214439
2007-01-01	27.1213003501936
2007-04-01	25.6485104033377
2007-07-01	26.1594454796359
2007-10-01	26.1248770739117
2008-01-01	26.8189608111618
2008-04-01	25.5140112339818
2008-07-01	25.9315062894460
2008-10-01	25.9971179263732
2009-01-01	26.4897098773754
2009-04-01	25.5926459990537
2009-07-01	25.5719291172898
2009-10-01	25.9713280748368
2010-01-01	26.3443291736832
2010-04-01	25.5338304932122
2010-07-01	25.5155686494650
2010-10-01	25.7857229738671
2011-01-01	26.0246368253567
2011-04-01	24.7959106530959
2011-07-01	25.6058060964831
2011-10-01	25.9829809272503
2012-01-01	26.6303411613091
2012-04-01	25.6460414600330
2012-07-01	25.8680378460306
2012-10-01	25.9076957367279
2013-01-01	25.8242699540707
2013-04-01	24.8289073843050
2013-07-01	24.9493503416205
2013-10-01	24.6867099619532
2014-01-01	25.1291740927583
2014-04-01	24.1334438928594
2014-07-01	24.2025902090736
2014-10-01	24.1488193266281
2015-01-01	24.5290271046673
2015-04-01	23.8858721490108
2015-07-01	23.6520628197019
2015-10-01	23.5977332968500
2016-01-01	23.7140494309069
2016-04-01	23.0283293248783
2016-07-01	22.6704261399767
2016-10-01	22.7318599346359
2017-01-01	23.2137511208453
2017-04-01	22.2402451928872
2017-07-01	22.0041914721046
2017-10-01	22.0336988945008
2018-01-01	21.8388833887216
2018-04-01	20.9861959686343
2018-07-01	20.8082607942450