Year Number 2004-01-01 5.2745 2005-01-01 6.0444 2006-01-01 5.8046 2007-01-01 5.7776 2008-01-01 5.8010 2009-01-01 5.6710 2010-01-01 5.6853 2011-01-01 5.4673 2012-01-01 5.3428 2013-01-01 5.3127 2014-01-01 5.1972 2015-01-01 5.1402 2016-01-01 5.0463