Year Percent 1993 1.05514 1997 1.07982 1998 1.04479 1999 1.00644 2000 1.03499 2006 0.99689 2010 1.00519 2011 1.00623 2012 1.00784 2013 1.01306 2014 1.01562 2015 1.02118 2016 1.01626 2017 1.0123