Year Percent 1989 90.78728 1990 95.89328 1991 68.71287 1992 60.12941 1993 57.55914 1994 31.0961 1995 34.80281 1996 37.60139 1997 46.17348 1998 44.54975 1999 49.57043 2000 47.97028 2001 44.40982 2002 44.31289 2003 46.66978 2004 51.20878 2005 72.93126 2006 78.89798 2007 83.18855 2008 85.46933 2009 76.15414 2010 91.83065 2011 107.29343 2012 108.84921 2013 104.53637 2014 101.60803 2015 94.49027 2016 89.82965 2017 89.0356