Year Percent 1995 39.3 1996 40.99 1997 37.86 1998 33.38 1999 28.75 2000 31.71 2001 34.58 2002 34.98 2003 32.57 2004 37.82 2005 31.21 2006 32.92 2007 30.52 2008 31.68 2009 30.39 2010 34.39