Year Percent 1960-01-01 9.99519 1961-01-01 10.01550 1962-01-01 9.94610 1963-01-01 10.25660 1964-01-01 10.68180 1965-01-01 11.91080 1966-01-01 13.86200 1967-01-01 16.26550 1968-01-01 17.88670 1969-01-01 20.01140 1970-01-01 14.36350 1971-01-01 15.28250 1972-01-01 15.17030 1973-01-01 16.04600 1974-01-01 17.42000 1975-01-01 19.20020 1976-01-01 19.54140 1977-01-01 20.31470 1978-01-01 21.01730 1979-01-01 20.85310 1980-01-01 20.66340 1981-01-01 20.16450 1982-01-01 21.45550 1983-01-01 22.50440 1984-01-01 22.81400 1985-01-01 22.99970 1986-01-01 24.38600 1987-01-01 24.84220 1988-01-01 24.39300 1989-01-01 23.46840 1990-01-01 21.47130 1991-01-01 19.07170 1992-01-01 18.60510 1993-01-01 18.55110 1994-01-01 17.60450 1995-01-01 16.88410 1996-01-01 17.62770 1997-01-01 21.64860 1998-01-01 27.21440 1999-01-01 31.77970 2000-01-01 32.21690 2001-01-01 34.01350 2002-01-01 35.01470 2003-01-01 35.34540 2004-01-01 36.14650 2005-01-01 37.10140 2006-01-01 40.26420 2007-01-01 46.25090 2008-01-01 50.47540 2009-01-01 50.69110 2010-01-01 47.77860 2011-01-01 45.68580 2012-01-01 48.02310 2013-01-01 52.45070 2014-01-01 53.21790 2015-01-01 52.91530 2016-01-01 54.42670