Year Ratio 1999-01-01 0.981570005416870 2000-01-01 0.966870009899139 2001-01-01 0.969399988651276 2002-01-01 0.947759985923767 2003-01-01 0.931500017642975 2004-01-01 0.923409998416901 2005-01-01 0.938030004501343 2006-01-01 0.955470025539398 2007-01-01 0.956110000610352 2008-01-01 0.960789978504181 2009-01-01 0.971279978752136 2010-01-01 0.986959993839264 2011-01-01 0.971710026264191 2012-01-01 1.025079965591430 2013-01-01 0.978100001811981 2014-01-01 0.968640029430389