Year Percent 1977-01-01 3.78706999999999950 1978-01-01 3.72316000000000000 1979-01-01 3.66305999999999980 1980-01-01 1.41306000000000000 1981-01-01 1.18144000000000000 1982-01-01 1.30854000000000000 1983-01-01 1.31842000000000010 1984-01-01 1.19676000000000000 1985-01-01 1.51341000000000010 1986-01-01 1.47694000000000000 1987-01-01 1.52907000000000020 1988-01-01 1.72969000000000020 1989-01-01 1.72511000000000000 1990-01-01 1.70501000000000000 1991-01-01 1.52799000000000000 1992-01-01 1.27326000000000000 1993-01-01 1.23768000000000000 1994-01-01 1.19591000000000000 1995-01-01 1.16986000000000010 1996-01-01 0.87331000000000000 1997-01-01 0.60221300000000000 1998-01-01 0.50278700000000000 1999-01-01 0.39817800000000003 2000-01-01 0.13328900000000002 2001-01-01 0.58470600000000010 2002-01-01 0.65105400000000000 2003-01-01 0.77990500000000010 2004-01-01 0.72535300000000000 2005-01-01 0.79148000000000010 2006-01-01 1.65641000000000000 2007-01-01 1.66839000000000000 2008-01-01 1.50263000000000000 2009-01-01 1.24278000000000000 2010-01-01 1.39265000000000000 2011-01-01 1.06152000000000000 2012-01-01 1.01633000000000000 2013-01-01 1.01184000000000000 2014-01-01 1.51518000000000000 2015-01-01 1.02033000000000000 2016-01-01 0.86854400000000010 2017-01-01 0.86225100000000000