Year Measure 1971 776.69094 1972 802.21249 1973 770.5797 1974 813.18345 1975 742.17572 1976 779.95924 1977 805.37456 1978 846.1425 1979 888.89946 1980 915.03579 1981 930.57662 1982 897.13732 1983 914.93697 1984 974.33115 1985 994.33315 1986 1033.25972 1987 1058.50774 1988 1124.90998 1989 1211.82604 1990 1240.66125 1991 1317.65464 1992 1462.28891 1993 1521.5375 1994 1597.1456 1995 1755.66059 1996 1938.42856 1997 2082.22821 1998 2190.12187 1999 2406.58722 2000 2512.3251 2001 2640.7952 2002 2738.47923 2003 2906.983 2004 3072.34769 2005 3102.48352 2006 3229.2691 2007 3347.26217 2008 3347.56897 2009 3307.65571 2010 3320.41573 2011 3600.34482 2012 3827.43918 2013 3903.97241 2014 3911.64926