Year % 1972 86.52793 1974 92.85403 1975 77.68491 1976 70.7264 1977 84.68066 1979 89.10846 1980 92.70453 1982 100 1983 85.34613 2002 87.36521 2003 97.72262 2004 96.56265 2005 99.89629 2006 100 2007 99.85816 2008 100 2009 99.28104 2010 100 2011 99.24229 2012 100 2013 99.49669 2014 100 2016 100 2017 100