Year % 1998 91.71903 1999 96.58803 2000 93.65213 2001 92.95913 2002 92.68785 2003 91.97885 2004 90.40371 2006 88.37674 2007 89.12541 2008 90.01479 2009 91.66553 2010 92.5832 2011 94.53467