Year Percent 1995 31.31 1996 35.42 1997 30.18 1998 38.11 1999 34.51 2000 32.31 2001 34.11 2002 33.33 2003 15.2 2004 24.93 2005 19.15 2006 20.14 2007 17.71 2008 17.95 2009 21.02 2010 21.89