Year Percent 1996 1.0271 1997 1.09732 1998 0.94463 1999 0.95509 2000 0.62642 2001 0.57932 2002 0.59088 2003 1.0455 2004 1.25327 2005 1.39436 2006 1.24075 2007 1.11723 2008 0.89947 2009 1.07923 2010 1.48347 2011 1.36361 2012 1.25858 2013 1.36405 2014 1.52946 2015 1.462 2016 1.54487 2017 1.41361