Year Percent 1971 95.60695 1972 92.49302 1973 93.83873 1974 92.67747 1975 94.18851 1976 101.27813 1977 100.74891 1978 108.11135 1979 109.42116 1980 102.22899 1981 93.27627 1982 91.28052 1983 92.1761 1984 97.77244 1985 99.98391 1986 97.04543 1987 98.41899 1988 102.33848 1989 97.65247 1990 95.36968 1991 97.75566 1992 97.01695 1993 99.28284 1994 96.84341 1998 101.62769 1999 101.44978 2000 100.14678 2001 101.35879 2002 105.41577 2004 100.65758 2005 100.35957 2006 102.03966 2007 101.75592 2008 100.96915 2009 97.97162 2010 99.1185 2011 99.62967 2012 98.26137 2013 99.28279 2014 98.78085 2015 98.74251 2016 103.88269