Year Measure 1995 4.12 1996 4.86 1997 5.18 1998 5 1999 5.2 2000 5.2 2001 5.3 2002 4.9 2003 4.8 2004 4.8 2005 5 2006 5.2 2007 5.3 2008 5.1 2009 5.1 2010 4.7 2011 4.55545