Year Measure 1965 1135.00924 1966 1219.51303 1967 1306.30491 1968 1380.0951 1969 1467.36639 1970 1588.61898 1971 1711.30327 1972 1827.76555 1973 1955.51116 1974 2070.1956 1975 2148.37496 1976 2284.24736 1977 2418.56922 1978 2611.18061 1979 2638.69571 1980 2697.75659 1981 2738.55641 1982 2833.48754 1983 2950.66272 1984 3103.83438 1985 3194.09491 1986 3268.31201 1987 3424.65721 1988 3426.22984 1989 3484.35214 1990 3426.5511 1991 3223.91887 1992 3116.01287 1993 2995.98659 1994 3025.71071 1995 3066.52215 1996 3162.37488 1997 3188.38197 1998 3215.67963 1999 3321.40663 2000 3309.28371 2001 3426.7229 2002 3545.17076 2003 3637.27833 2004 3680.16847 2005 3771.36461 2006 3882.49066 2007 3976.51898 2008 3988.76769 2009 3773.15381 2010 3876.49108 2011 3898.82314 2012 3923.04232 2013 3892.1137 2014 3965.95823