Year	Percent
1991-01-01	62.7109985351563
1992-01-01	63.8759994506836
1993-01-01	64.0500030517578
1994-01-01	64.0780029296875
1995-01-01	64.1679992675781
1996-01-01	63.5940017700195
1997-01-01	64.5299987792969
1998-01-01	64.2760009765625
1999-01-01	64.5110015869141
2000-01-01	63.1269989013672
2001-01-01	61.6689987182617
2002-01-01	60.5180015563965
2003-01-01	58.5929985046387
2004-01-01	57.0600013732910
2005-01-01	56.5999984741211
2006-01-01	59.3689994812012
2007-01-01	60.4140014648438
2008-01-01	61.2579994201660
2009-01-01	61.9799995422363
2010-01-01	61.6769981384277
2011-01-01	60.0359992980957
2012-01-01	59.0309982299805
2013-01-01	60.8979988098145
2014-01-01	62.0369987487793
2015-01-01	64.7389984130859
2016-01-01	64.9489974975586
2017-01-01	65.0459976196289