Year Measure 1990 4492.85307 1991 4555.89751 1992 4796.14425 1993 4018.4694 1994 3612.13807 1995 3303.26767 1996 2911.34437 1997 2575.6706 1998 2610.07863 1999 2406.24892 2000 2397.20233 2001 2324.54767 2002 2674.25567 2003 2891.09303 2004 3383.07445 2005 3358.97112 2006 4012.78507 2007 4267.99306 2008 4457.16811 2009 3944.28827 2010 4234.85106 2011 4670.82123 2012 4398.94441 2013 4786.59304 2014 4434.63912