Year Percent 1975-01-01 34.03070000000000 1976-01-01 29.57260000000000 1977-01-01 31.91650000000000 1978-01-01 35.24680000000000 1979-01-01 44.00230000000000 1980-01-01 47.97080000000000 1981-01-01 47.89960000000000 1982-01-01 49.88480000000000 1983-01-01 56.49110000000000 1984-01-01 64.37590000000000 1985-01-01 69.35010000000000 1986-01-01 65.63090000000000 1987-01-01 70.33000000000000 1988-01-01 71.62380000000000 1989-01-01 79.55850000000000 1990-01-01 73.29760000000000 1991-01-01 74.05250000000000 1992-01-01 64.29640000000000 1993-01-01 70.23230000000000 1994-01-01 73.88170000000000 1995-01-01 75.55430000000000 1996-01-01 80.83760000000000 1997-01-01 79.52350000000000 1998-01-01 78.57620000000000 1999-01-01 83.37970000000000 2000-01-01 86.40240000000000 2001-01-01 89.53770000000000 2002-01-01 90.41450000000000 2003-01-01 86.89020000000000 2004-01-01 85.66490000000000 2005-01-01 96.36330000000000 2006-01-01 101.84700000000001 2007-01-01 107.14299999999999 2008-01-01 105.02700000000000 2009-01-01 102.16700000000000 2010-01-01 99.16860000000000 2011-01-01 101.62200000000001 2012-01-01 107.49799999999999 2013-01-01 110.30600000000000 2014-01-01 111.57799999999999 2015-01-01 110.31500000000000 2016-01-01 111.73400000000000