Year Measure 1971 505.75194 1972 514.99673 1973 547.40318 1974 571.74307 1975 623.19607 1976 671.18798 1977 721.56003 1978 788.55843 1979 863.63399 1980 841.266 1981 964.46728 1982 1008.29943 1983 1052.80236 1984 1117.99282 1985 1004.2657 1986 1075.22683 1987 1093.13275 1988 1149.37568 1989 1187.23972 1990 1214.03342 1991 1049.83455 1992 904.74905 1993 839.80791 1994 897.46313 1995 917.83977 1996 972.53794 1997 1037.9533 1998 1043.01327 1999 1078.03742 2000 1135.44075 2001 1155.58499 2002 1183.18794 2003 1191.74185 2004 1173.61048 2005 1152.75686 2006 1223.41669 2007 1296.39117 2008 1314.88271 2009 1323.92675 2010 1290.82627 2011 1318.66669 2012 1364.06614 2013 1419.27471 2014 1434.0327