Year % 1971 93.70845 1972 98.83556 1973 96.33895 1974 96.2483 1975 100 1976 98.51782 1977 98.18182 1978 100 1982 100 1984 96.07619 1985 98.66444 1986 100 1987 98.55471 1988 99.24812 1989 98.41994 1990 97.55752 1991 99.86699 1992 98.00944 1993 89.42806 1994 100 1995 100 1996 100 1997 98.02657 1998 100 1999 99.41013 2000 99.44828 2001 97.36149 2002 99.92819 2004 100 2005 98.1125 2006 94.97748 2007 99.56507 2010 98.08044 2011 100 2012 97.83356 2014 93.6745 2015 97.14555 2016 97.74222