Year Percent 1982-01-01 0.1726650000000000 1983-01-01 0.3329510000000000 1984-01-01 1.0134700000000000 1985-01-01 1.4697200000000001 1986-01-01 1.4808600000000000 1987-01-01 2.6674599999999997 1988-01-01 2.6562600000000000 1989-01-01 2.1150700000000002 1990-01-01 1.2626500000000000 1991-01-01 1.2959800000000000 1992-01-01 1.0509899999999999 1993-01-01 1.5343900000000000 1994-01-01 1.4905700000000002 1995-01-01 1.3641200000000000 1996-01-01 1.8603200000000000 1997-01-01 2.7147000000000000 1998-01-01 2.9793100000000000 1999-01-01 8.9267399999999990 2000-01-01 16.7138000000000000 2001-01-01 26.2971000000000000 2002-01-01 34.8254000000000000 2003-01-01 42.9486000000000000 2004-01-01 46.8095000000000000 2005-01-01 46.7836000000000000 2006-01-01 60.9461000000000000 2007-01-01 68.6359000000000000 2008-01-01 65.7370000000000000 2009-01-01 86.5729000000000000 2010-01-01 78.3723000000000000 2011-01-01 69.2434000000000000 2012-01-01 68.9114000000000000 2013-01-01 63.5471000000000000 2014-01-01 48.3011000000000000 2015-01-01 46.0063000000000000 2016-01-01 40.1787000000000000