Year Measure 1960 1825.93425 1961 1879.1502 1962 2081.01162 1963 2268.42789 1964 2349.08354 1965 2493.1539 1966 2605.56696 1967 2762.80248 1968 3042.80966 1969 3362.78722 1970 3765.56737 1971 3855.22677 1972 4381.04179 1973 4613.27134 1974 4501.41432 1975 4318.72656 1976 4742.98174 1977 4560.27312 1978 4662.60528 1979 4868.63559 1980 4548.82479 1981 4269.41412 1982 3785.11594 1983 3935.95688 1984 4147.70153 1985 4184.42981 1986 4317.31559 1987 4387.67069 1988 4321.10053 1989 4323.85818 1990 4394.54209 1991 4603.73318 1992 4502.54008 1993 4510.58215 1994 4511.79496 1995 4780.4126 1996 5014.98883 1997 4835.74195 1998 4842.44394 1999 4730.22968 2000 4739.06593 2001 4839.46553 2002 4873.26163 2003 5020.38193 2004 5085.8857 2005 4989.46793 2006 4925.11242 2007 4908.89826 2008 4848.01369 2009 4722.10604 2010 5025.32092 2011 4636.7019 2012 4646.25524 2013 4600.18298 2014 4325.52371 2015 4233.04386