Year Measure 1971 93.55449 1972 91.03616 1973 101.31704 1974 107.3672 1975 111.24769 1976 107.94437 1977 110.22432 1978 121.77072 1979 139.82168 1980 136.02219 1981 147.70076 1982 159.26494 1983 171.0012 1984 183.61754 1985 198.82999 1986 214.11973 1987 228.28972 1988 255.42293 1989 264.38856 1990 277.35312 1991 297.31667 1992 333.88973 1993 334.89634 1994 345.36322 1995 357.92807 1996 359.46957 1997 362.99554 1998 344.25615 1999 356.167 2000 372.39949 2001 378.18825 2002 384.78677 2003 409.8213 2004 429.10778 2005 463.05733 2006 486.79137 2007 480.98652 2008 442.70938 2009 458.83982 2010 465.16132 2011 455.32241 2012 450.38115 2013 481.87634 2014 471.04157