Year Percent 1995-01-01 22.1977000000000000 1996-01-01 23.2396000000000000 1997-01-01 15.5518000000000000 1998-01-01 11.8538000000000000 1999-01-01 15.6983000000000000 2000-01-01 9.3937400000000000 2001-01-01 10.2179000000000000 2002-01-01 8.8867800000000000 2003-01-01 15.2449000000000000 2004-01-01 10.4099000000000000 2005-01-01 6.3234400000000000 2006-01-01 5.4336800000000010 2007-01-01 4.9659200000000000 2008-01-01 3.0321400000000000 2009-01-01 2.8668299999999998 2010-01-01 2.5935400000000000 2011-01-01 2.3084100000000000 2012-01-01 2.8358900000000000 2013-01-01 3.7154300000000005 2014-01-01 3.2427400000000000 2015-01-01 3.4148900000000000 2016-01-01 2.1788000000000000