Year Percent 1995-01-01 5.56384558150000 1996-01-01 5.81267211100000 1997-01-01 6.81580350000000 1998-01-01 8.00042780600000 1999-01-01 8.46594057400000 2000-01-01 8.43129401575000 2001-01-01 8.89787125850000 2002-01-01 10.05163330375000 2003-01-01 10.19230953450000 2004-01-01 9.50104438100000 2005-01-01 8.52253121100000 2006-01-01 7.89487300750000 2007-01-01 6.77482191675000 2008-01-01 5.74694061300000 2009-01-01 7.54952905600000 2010-01-01 6.76451492375000 2011-01-01 5.58963101075000 2012-01-01 6.75000000000000 2013-01-01 6.19166666666667 2014-01-01 5.85833333333333 2015-01-01 5.11666666666667 2016-01-01 4.65833333333333 2017-01-01 4.12500000000000