Year Percent 1995-01-01 43.1855050572599 1996-01-01 43.4709318355076 1997-01-01 44.4940794382265 1998-01-01 45.3128280871854 1999-01-01 46.7507206868087 2000-01-01 48.0969865313173 2001-01-01 48.1877776085265 2002-01-01 50.0254677432879 2003-01-01 53.0261432737209 2004-01-01 53.9077740485720 2005-01-01 54.8005088321577 2006-01-01 55.5346947493374 2007-01-01 56.9898611715276 2008-01-01 57.2216291583279 2009-01-01 57.2841833877455 2010-01-01 58.0539371265943 2011-01-01 58.3942238317665 2012-01-01 59.4038968145909 2013-01-01 60.3104654376559 2014-01-01 60.4317562661926 2015-01-01 60.8650984516263 2016-01-01 61.6301463980468 2017-01-01 62.1917109067252