Year % 1970 33.97587 1998 98.00418 1999 99.96619 2000 100 2001 99.56317 2002 98.97367 2003 100 2004 100 2005 100 2006 100 2007 100 2008 100 2009 100 2010 100 2011 100 2012 100 2013 100 2014 100 2015 100 2016 99.69746