Year Percent 1995 39.23 1996 46.85 1997 44.75 1998 46.9 1999 45.9 2000 49.76 2001 53.31 2002 55.04 2003 57.73 2004 55.82 2005 55.99 2006 50.48 2007 47.14 2008 44.99 2009 41.54 2010 37.81