Year Measure 1971 909.07734 1972 936.4949 1973 963.29519 1974 990.52926 1975 1018.75667 1976 1033.23844 1977 1049.6781 1978 1066.99683 1979 1083.9732 1980 1098.94953 1981 1112.33118 1982 1123.6876 1983 1134.42766 1984 1145.715 1985 1204.14862 1986 1188.61219 1987 1209.34628 1988 1282.09792 1989 1323.96341 1990 1237.41848 1991 1156.86479 1992 1024.48231 1993 902.48048 1994 925.85118 1995 905.94315 1996 825.60248 1997 736.98365 1998 637.51989 1999 692.76836 2000 712.37065 2001 735.22133 2002 713.46907 2003 751.06612 2004 779.62037 2005 807.01411 2006 785.04318 2007 748.6999 2008 802.83061 2009 727.09744 2010 741.67605 2011 654.7126 2012 651.56425 2013 617.66649 2014 600.28596