Year Percent 1987-01-01 1.1945200000000000 1988-01-01 1.0546100000000000 1989-01-01 1.0104799999999998 1990-01-01 1.2066900000000000 1991-01-01 1.2448900000000000 1992-01-01 1.1250799999999999 1993-01-01 1.2910900000000000 1994-01-01 1.8456000000000000 1995-01-01 1.4495200000000001 1996-01-01 1.2259400000000000 1997-01-01 1.3987200000000000 1998-01-01 1.2263899999999999 1999-01-01 1.2003600000000000 2000-01-01 1.0539800000000000 2001-01-01 0.9319540000000001 2002-01-01 0.8943370000000000 2003-01-01 0.8840110000000001 2004-01-01 0.9247040000000001 2005-01-01 0.9235820000000000 2006-01-01 0.8495600000000000 2007-01-01 0.9511920000000000 2008-01-01 0.9257230000000000 2009-01-01 0.8429690000000001 2010-01-01 1.0853500000000000 2011-01-01 1.4680700000000000 2012-01-01 1.8584300000000000 2013-01-01 2.6811100000000000 2014-01-01 3.9767800000000000 2015-01-01 4.5791500000000000 2016-01-01 5.5324900000000000