Year Percent 1996-01-01 45.6577 1997-01-01 49.3309 1998-01-01 45.7128 1999-01-01 41.5599 2000-01-01 58.0709 2001-01-01 64.8566 2002-01-01 51.1498 2003-01-01 47.2937 2004-01-01 46.5087 2005-01-01 38.6386 2006-01-01 42.3787 2007-01-01 47.3518 2008-01-01 68.9329 2009-01-01 61.3624 2010-01-01 58.4357 2011-01-01 50.2619 2012-01-01 50.2534 2013-01-01 45.8537 2014-01-01 51.1476