Year Percent 1997 6.75906 1998 8.62972 1999 7.66954 2000 8.32372 2001 5.61211 2002 4.87553 2003 4.69231 2004 4.61148 2005 3.65647 2006 3.22597 2007 3.28052 2008 3.66802 2009 5.45711 2010 6.03859 2011 5.46631 2012 5.07556 2013 6.03469 2014 5.64365