Year % 1982 85.78278 1983 87.0448 1984 86.89175 1985 89.87647 1986 89.23927 1987 88.93952 1988 88.53563 1989 87.96016 1990 83.74245 1991 83.64452 1992 83.27722 1993 83.86356 1994 84.52689 1995 85.28653 1996 85.56366 1997 86.40322 1998 87.24316 1999 87.56569 2000 89.51844 2001 86.85013 2002 89.19348 2003 89.96465 2004 90.27621 2005 91.03467 2006 92.21379 2007 94.53474 2008 92.92741 2009 94.72295 2010 93.72743 2011 92.87353 2012 91.52026 2013 93.17855 2014 90.96223 2015 91.27227 2016 91.72793 2017 93.27782