Year Percent 1997-01-01 6.6666700000000000 1998-01-01 6.6666700000000000 1999-01-01 6.6666700000000000 2000-01-01 6.6666700000000000 2001-01-01 5.9259300000000000 2002-01-01 4.2639600000000000 2003-01-01 3.6139300000000003 2004-01-01 3.5985600000000000 2005-01-01 4.1981000000000000 2006-01-01 3.8177300000000005 2007-01-01 4.4324600000000000 2008-01-01 4.9376700000000000 2009-01-01 3.2986100000000000 2010-01-01 3.1496100000000000 2011-01-01 6.1780100000000000 2012-01-01 4.9441800000000000 2013-01-01 5.3767500000000000 2014-01-01 4.9019600000000000 2015-01-01 5.2231200000000000 2016-01-01 4.2170400000000000