Year Percent 1994-01-01 42.07 1995-01-01 44.70 1996-01-01 48.51 1997-01-01 51.44 1998-01-01 54.47 1999-01-01 58.94 2000-01-01 58.10 2001-01-01 56.24 2002-01-01 55.76 2003-01-01 59.64 2004-01-01 62.62 2005-01-01 68.70 2006-01-01 68.80 2007-01-01 69.05 2008-01-01 69.61 2009-01-01 104.98 2010-01-01 110.34 2011-01-01 120.72 2012-01-01 127.90 2013-01-01 129.43 2014-01-01 143.53 2015-01-01 144.43