Year % 1973 84.68076 1974 99.58264 1975 85.06637 1976 96.02856 1977 93.45902 1979 93.47351 1982 98.2274 1983 98.59707 1984 94.61909 1985 96.98659 1986 97.54011 1987 99.41766 1988 100 1989 99.16157 1990 97.6171 1991 92.94149 1992 96.0513 1993 98.99334 1994 97.76635 1996 97.65106 1999 98.46648 2000 100 2001 98.04543 2002 96.14125 2003 99.54714 2004 99.04643 2005 100 2006 100 2009 95.52038 2010 91.77475 2011 98.8909 2012 98.10216 2013 100