Year Percent 1995 26.12 1996 28.56 1997 29.21 1998 34.91 1999 38.14 2000 40.12 2001 41.34 2002 41.05 2003 41.19 2004 40.42 2005 38.02 2006 36.77 2007 35.82 2008 35.69 2009 36.65 2010 37.92