Year Measure 1995 3.44 1996 2.73 1997 2.23 1998 2.2 1999 2.9 2000 3.2 2001 3.8 2002 3.6 2003 3.7 2004 3.8 2005 4 2006 3.9 2007 3.8 2008 3.8 2009 3.7 2010 3.5 2011 3.44667