Year Ratio 1970-01-01 1.00018 1971-01-01 1.00089 1972-01-01 1.00274 1973-01-01 1.01565 1974-01-01 0.99927 1975-01-01 0.99991 1976-01-01 1.01529 1977-01-01 0.99709 1978-01-01 0.99730 1979-01-01 0.99401 1980-01-01 0.99669 1981-01-01 0.99660 1982-01-01 0.99713 1983-01-01 0.99706 1984-01-01 0.99664 1985-01-01 0.99322 1986-01-01 0.99207 1987-01-01 0.99479 1988-01-01 0.99000 1989-01-01 0.99258 1990-01-01 0.99521 1991-01-01 0.99630 1992-01-01 0.99554 1993-01-01 0.99604 1994-01-01 0.99283 1995-01-01 0.98686 1996-01-01 0.98678 1997-01-01 0.98964 1998-01-01 0.98836 1999-01-01 0.98875 2000-01-01 0.99081 2001-01-01 0.99105 2002-01-01 0.98787 2003-01-01 0.98844 2004-01-01 0.98924 2005-01-01 0.98780 2006-01-01 0.98719 2007-01-01 0.98777 2008-01-01 0.98790 2009-01-01 0.99037 2010-01-01 0.99183 2011-01-01 0.99356 2012-01-01 0.99511 2013-01-01 0.99632 2014-01-01 0.99649 2015-01-01 0.99698 2016-01-01 0.99761