Year Percent 1993-01-01 12.2449000000000000 1994-01-01 10.8638000000000000 1995-01-01 9.8878500000000000 1996-01-01 9.9067300000000000 1997-01-01 9.0604500000000000 1998-01-01 8.5089399999999990 1999-01-01 7.9756700000000000 2000-01-01 7.7634399999999990 2001-01-01 7.0736700000000000 2002-01-01 6.6213399999999990 2003-01-01 0.1839780000000000 2004-01-01 1.3255100000000000 2005-01-01 1.1240900000000000 2006-01-01 0.9343969999999999 2007-01-01 0.8195620000000001 2008-01-01 0.6671420000000000 2009-01-01 0.5949570000000000 2010-01-01 3.2849800000000005 2011-01-01 3.0456100000000000 2012-01-01 2.7996000000000000 2013-01-01 6.2817500000000000 2014-01-01 8.7411600000000000 2015-01-01 11.7479000000000000 2016-01-01 13.7716000000000000