Quarter	Percent
1978-04-01	13.0397233781631
1978-07-01	13.7584238599329
1978-10-01	13.3442452457454
1979-01-01	12.8879598951168
1979-04-01	13.4400605529341
1979-07-01	13.7575156620468
1979-10-01	13.4002030436232
1980-01-01	12.9946191140206
1980-04-01	13.4074850629280
1980-07-01	13.4871400225233
1980-10-01	13.2917880787939
1981-01-01	12.8910314891368
1981-04-01	13.5450543351668
1981-07-01	13.6222929230881
1981-10-01	13.8142619913578
1982-01-01	13.3205735062543
1982-04-01	14.2218095079820
1982-07-01	14.3389153407486
1982-10-01	13.9997310774811
1983-01-01	13.9943938281182
1983-04-01	14.8331035348116
1983-07-01	14.9607623247307
1983-10-01	14.9782800553396
1984-01-01	14.4589411732511
1984-04-01	15.0690490145671
1984-07-01	15.3832234181554
1984-10-01	15.6310641458857
1985-01-01	15.1842360001867
1985-04-01	15.8863207355160
1985-07-01	15.7224211882223
1985-10-01	15.4365674725248
1986-01-01	14.7955235128989
1986-04-01	15.2347323558645
1986-07-01	15.4938045251595
1986-10-01	15.3065453703868
1987-01-01	15.0983419748627
1987-04-01	15.6547829037303
1987-07-01	15.8612356953142
1987-10-01	15.9637845038553
1988-01-01	15.2545007602695
1988-04-01	15.5115157405199
1988-07-01	16.1456925231751
1988-10-01	15.7292047117313
1989-01-01	15.3127268955250
1989-04-01	15.4187709724949
1989-07-01	15.3457182078325
1989-10-01	15.1467079814099
1990-01-01	15.0743553000451
1990-04-01	15.0860214267867
1990-07-01	14.9470025918091
1990-10-01	14.8731149781156
1991-01-01	15.1006344187113
1991-04-01	15.7254289162002
1991-07-01	16.3855791735219
1991-10-01	16.0755785605109
1992-01-01	15.7861607049441
1992-04-01	16.3765906930229
1992-07-01	16.3783911554506
1992-10-01	16.4515914456059
1993-01-01	16.1430948286852
1993-04-01	16.8894019713541
1993-07-01	16.9519752927671
1993-10-01	16.3596536384931
1994-01-01	16.0552027065444
1994-04-01	16.7556830667635
1994-07-01	16.6565955653084
1994-10-01	16.5079977074195
1995-01-01	16.0190661218763
1995-04-01	16.3846562775131
1995-07-01	16.2556908155306
1995-10-01	16.0690036209376
1996-01-01	15.8524526465030
1996-04-01	16.4782634633542
1996-07-01	16.4650992616698
1996-10-01	16.4219822810326
1997-01-01	16.2413602463760
1997-04-01	17.0663342891313
1997-07-01	17.3546255635454
1997-10-01	16.9918302212918
1998-01-01	16.8322188225338
1998-04-01	17.2686208523365
1998-07-01	17.2266758764350
1998-10-01	17.2408675462379
1999-01-01	17.2487098045957
1999-04-01	17.6760278576164
1999-07-01	17.5839645062907
1999-10-01	17.5042203910837
2000-01-01	17.6378001967962
2000-04-01	17.7506941853180
2000-07-01	17.6088554421938
2000-10-01	17.6970327114105
2001-01-01	17.9256408627770
2001-04-01	17.8288835634518
2001-07-01	17.8266231607393
2001-10-01	17.6832630347170
2002-01-01	17.5393527477800
2002-04-01	17.8770881352296
2002-07-01	18.1533232307997
2002-10-01	17.8257490235452
2003-01-01	17.4874725305525
2003-04-01	18.2734738235641
2003-07-01	18.4686431154829
2003-10-01	17.8931536569005
2004-01-01	17.7818136654678
2004-04-01	18.0032625874804
2004-07-01	18.2937806118325
2004-10-01	17.8677780892668
2005-01-01	17.4391195352702
2005-04-01	17.3014014949980
2005-07-01	17.4496439510943
2005-10-01	17.3405630011590
2006-01-01	17.1626259192804
2006-04-01	17.4595705037562
2006-07-01	17.2062868526131
2006-10-01	17.1954018401502
2007-01-01	17.0759372573508
2007-04-01	17.0601324535183
2007-07-01	17.1892709268550
2007-10-01	16.8166066719377
2008-01-01	16.7239151867430
2008-04-01	16.8672665628112
2008-07-01	17.2050133153320
2008-10-01	17.0220450487307
2009-01-01	17.0409052106108
2009-04-01	17.3423797498331
2009-07-01	17.7321718181551
2009-10-01	17.4336113239955
2010-01-01	17.0125552182098
2010-04-01	17.3519872176591
2010-07-01	17.3679135237026
2010-10-01	16.6785189065552
2011-01-01	16.6313251451027
2011-04-01	17.2685180781764
2011-07-01	17.4293419295214
2011-10-01	17.2986841427223
2012-01-01	17.3053432935144
2012-04-01	17.6322173534355
2012-07-01	17.7563246128707
2012-10-01	17.3862924656938
2013-01-01	17.2291136934028
2013-04-01	17.4960994277075
2013-07-01	17.9266143822806
2013-10-01	17.8242514427703
2014-01-01	17.7599614076815
2014-04-01	18.0253939076811
2014-07-01	18.0893516831755
2014-10-01	17.6555879082946
2015-01-01	16.9739523168597
2015-04-01	17.3383189517211
2015-07-01	17.6223416569939
2015-10-01	17.3114062019008
2016-01-01	17.0926016947347
2016-04-01	17.6869335439057
2016-07-01	18.1538969690392
2016-10-01	17.7453376329642
2017-01-01	17.5091462981478
2017-04-01	17.4184310737447
2017-07-01	17.5654562537438
2017-10-01	17.0872152991984
2018-01-01	16.8103895553512
2018-04-01	17.1052526178066
2018-07-01	17.4542658612585