Year Percent 1995-01-01 42.0074000000000000 1996-01-01 27.4183000000000000 1997-01-01 28.8174000000000000 1998-01-01 11.3451000000000000 1999-01-01 13.1404000000000000 2000-01-01 15.7525000000000000 2001-01-01 13.7500000000000000 2002-01-01 12.0745000000000000 2003-01-01 9.0498200000000000 2004-01-01 11.9833000000000000 2005-01-01 11.9792000000000000 2006-01-01 14.9146000000000000 2007-01-01 12.4539000000000000 2008-01-01 10.5196000000000000 2009-01-01 10.8411000000000000 2010-01-01 6.0234600000000000 2011-01-01 6.8266800000000005 2012-01-01 5.6400000000000000 2013-01-01 4.3019600000000000 2014-01-01 4.0068400000000000 2015-01-01 4.1938900000000010 2016-01-01 4.8646100000000000