Year Measure 1960 289.05707 1961 322.49058 1962 350.10126 1963 367.81143 1964 433.55934 1965 478.75586 1966 547.197 1967 607.70216 1968 652.0816 1969 725.52562 1970 872.78373 1971 984.04208 1972 1134.78649 1973 1322.76394 1974 1256.34873 1975 1298.20436 1976 1386.10047 1977 1469.54943 1978 1525.44354 1979 1597.92593 1980 1553.78162 1981 1505.27939 1982 1537.2777 1983 1599.07022 1984 1652.72998 1985 1766.76615 1986 1673.81805 1987 1791.83339 1988 1902.91445 1989 2093.11435 1990 2102.67769 1991 2094.6215 1992 2129.89452 1993 2090.76236 1994 2138.25195 1995 2147.13648 1996 2206.10389 1997 2282.13703 1998 2389.79315 1999 2390.08287 2000 2506.63995 2001 2578.11211 2002 2597.74829 2003 2666.45364 2004 2711.46679 2005 2753.0512 2006 2742.62996 2007 2734.75583 2008 2745.49346 2009 2649.6612 2010 2482.11012 2011 2407.76274 2012 2403.23047 2013 2128.01067 2014 2123.89789 2015 2182.07109