Year Measure 1960 904.565 1961 987.91884 1962 1062.17728 1963 1092.69992 1964 1167.04052 1965 1251.01169 1966 1361.54162 1967 1484.06446 1968 1592.74035 1969 1701.90148 1970 1806.83498 1971 1955.77043 1972 2111.74187 1973 2264.72845 1974 2413.2024 1975 2593.16431 1976 2741.24396 1977 2871.91491 1978 2988.07971 1979 3009.85465 1980 3076.41925 1981 2884.20823 1982 2900.12711 1983 3044.74966 1984 3159.8086 1985 3260.42619 1986 3384.36024 1987 3519.95969 1988 3568.53485 1989 3537.92388 1990 3272.30231 1991 3088.22894 1992 2961.39574 1993 2977.7121 1994 2993.17753 1995 3060.88887 1996 3159.04182 1997 3206.23778 1998 3206.59177 1999 3171.75738 2000 3256.18046 2001 3260.03326 2002 3208.39216 2003 3324.47139 2004 3416.11863 2005 3437.324 2006 3584.96219 2007 3661.6461 2008 3725.74878 2009 3590.83208 2010 3797.0923 2011 3879.54209 2012 3899.17664 2013 3938.25521 2014 3971.79976