Year Percent 1990-01-01 1.3559299999999999 1991-01-01 1.3280800000000000 1992-01-01 1.4978300000000000 1993-01-01 1.6434900000000001 1994-01-01 1.5546100000000000 1995-01-01 1.6766200000000000 1996-01-01 1.6052600000000001 1997-01-01 1.6884099999999997 1998-01-01 1.4339300000000000 1999-01-01 1.4299800000000000 2000-01-01 1.4966800000000000 2001-01-01 1.4753800000000000 2002-01-01 1.4683300000000000 2003-01-01 1.5129200000000000 2004-01-01 1.4870700000000001 2005-01-01 1.4794900000000000 2006-01-01 1.4517700000000000 2007-01-01 1.4930600000000000 2008-01-01 1.5081500000000000 2009-01-01 1.5585300000000000 2010-01-01 1.5938900000000000 2011-01-01 1.6316100000000000 2012-01-01 1.6736900000000001 2013-01-01 1.6682299999999999 2014-01-01 1.6915700000000000 2015-01-01 1.6653000000000000