Quarter	Percent
1978-04-01	31.0688872545488
1978-07-01	31.5671774953083
1978-10-01	31.2460996470811
1979-01-01	31.2011449658218
1979-04-01	31.4184524889688
1979-07-01	31.5837194140408
1979-10-01	30.8641755390256
1980-01-01	30.6875529061170
1980-04-01	30.6250162966130
1980-07-01	30.4526085047344
1980-10-01	30.3908735864112
1981-01-01	30.5365785377384
1981-04-01	30.6412993628132
1981-07-01	30.5836637181562
1981-10-01	30.5517802061567
1982-01-01	30.4919535840721
1982-04-01	30.9953319124709
1982-07-01	31.1983307256968
1982-10-01	30.6509900472588
1983-01-01	30.8975587526143
1983-04-01	31.2633869994332
1983-07-01	31.2884438497062
1983-10-01	31.0771286112151
1984-01-01	30.8750000931268
1984-04-01	30.7522534324746
1984-07-01	31.0912902875597
1984-10-01	30.8973832745082
1985-01-01	30.6137926117392
1985-04-01	30.8367234757930
1985-07-01	30.5714519917163
1985-10-01	29.9075204670179
1986-01-01	29.3580390354706
1986-04-01	28.9650534461396
1986-07-01	29.1751229212758
1986-10-01	28.7767382103797
1987-01-01	28.7659903540746
1987-04-01	28.8100162485422
1987-07-01	29.0688500700135
1987-10-01	28.8334440322953
1988-01-01	28.3198867538598
1988-04-01	28.1151083137871
1988-07-01	28.6285234754072
1988-10-01	28.0595099773059
1989-01-01	27.7487271612705
1989-04-01	27.3133318752290
1989-07-01	27.2220861867934
1989-10-01	26.7916441470893
1990-01-01	26.8006582792308
1990-04-01	26.4299726114973
1990-07-01	26.3915050066143
1990-10-01	26.3429747896100
1991-01-01	26.6976971983667
1991-04-01	26.7481958450726
1991-07-01	27.3760495157374
1991-10-01	27.2524757396178
1992-01-01	27.0064586724942
1992-04-01	27.2756522615483
1992-07-01	27.1927452036331
1992-10-01	27.2313339463286
1993-01-01	27.2466714626604
1993-04-01	27.8552986165640
1993-07-01	27.6755464247462
1993-10-01	26.8789104886615
1994-01-01	26.8012063376921
1994-04-01	27.1004685570342
1994-07-01	26.7550948301188
1994-10-01	26.5761893313477
1995-01-01	26.3009179106052
1995-04-01	26.1586613824026
1995-07-01	26.0471194748678
1995-10-01	25.6394350531871
1996-01-01	25.7576460859836
1996-04-01	26.1313836413796
1996-07-01	26.0152684405342
1996-10-01	25.9735526148912
1997-01-01	25.9787051909232
1997-04-01	26.4902808410542
1997-07-01	26.7135453300021
1997-10-01	26.4460256528086
1998-01-01	26.5880045914852
1998-04-01	26.5688183905941
1998-07-01	26.4069083593957
1998-10-01	26.3739720975533
1999-01-01	26.7382537161620
1999-04-01	26.8672897457430
1999-07-01	26.7135386324975
1999-10-01	26.3333385257249
2000-01-01	26.5420133718479
2000-04-01	26.1922684904842
2000-07-01	25.9039240882154
2000-10-01	26.1904406742205
2001-01-01	26.3573181644018
2001-04-01	25.7214514368405
2001-07-01	25.9386814663964
2001-10-01	25.7608358055751
2002-01-01	25.8154797643266
2002-04-01	26.1065797452558
2002-07-01	25.9888420870014
2002-10-01	25.4976427184307
2003-01-01	25.0991479557084
2003-04-01	25.5535099497536
2003-07-01	25.8490717399177
2003-10-01	25.5410905317396
2004-01-01	25.6927776612835
2004-04-01	25.7098430777816
2004-07-01	25.8321127062859
2004-10-01	25.2916412898733
2005-01-01	24.8307208530823
2005-04-01	24.5380416031628
2005-07-01	24.6070364859986
2005-10-01	24.4376499058406
2006-01-01	24.4050349105907
2006-04-01	24.2926209722298
2006-07-01	24.0826290345524
2006-10-01	24.0129118286477
2007-01-01	23.9707618370350
2007-04-01	23.8957182752569
2007-07-01	23.9046336422975
2007-10-01	23.4631763676032
2008-01-01	23.5136142381212
2008-04-01	23.3900604682804
2008-07-01	23.6259325328828
2008-10-01	23.4574207874729
2009-01-01	23.2705245952012
2009-04-01	23.4882757934479
2009-07-01	23.9946882556741
2009-10-01	23.7019716837430
2010-01-01	23.6593699374874
2010-04-01	23.8107367710630
2010-07-01	23.6938491231396
2010-10-01	23.0977073343167
2011-01-01	23.1518487916523
2011-04-01	23.4243609226849
2011-07-01	23.4501718962637
2011-10-01	23.3997635419633
2012-01-01	23.4882827643887
2012-04-01	23.5476326190247
2012-07-01	23.7467446323158
2012-10-01	23.5052080120779
2013-01-01	23.3722816154014
2013-04-01	23.4192247611868
2013-07-01	23.8297307137564
2013-10-01	23.7686688768810
2014-01-01	23.6400368622374
2014-04-01	23.7472369840589
2014-07-01	23.8247058069139
2014-10-01	23.5572026065217
2015-01-01	23.0966968308744
2015-04-01	23.1139181232590
2015-07-01	23.2813980095129
2015-10-01	22.7387283096873
2016-01-01	22.7303263062431
2016-04-01	22.9322826023253
2016-07-01	23.4761080572946
2016-10-01	23.0740450511597
2017-01-01	22.8927577412203
2017-04-01	22.6034708720133
2017-07-01	22.6956005799314
2017-10-01	22.0323688940827
2018-01-01	21.8027818372950
2018-04-01	21.8870813353328
2018-07-01	22.3298107292906