Year Percent 1992-01-01 0.00100000000000000 1993-01-01 0.48900000000000000 1994-01-01 0.52800000000000000 1995-01-01 0.17400000000000000 1996-01-01 0.27200000000000000 1997-01-01 0.31100000000000000 1998-01-01 0.25200000000000000 1999-01-01 0.38799999999999996 2000-01-01 0.90000000000000000 2001-01-01 1.56000000000000000 2002-01-01 2.75000000000000000 2003-01-01 3.94000000000000000 2004-01-01 4.74000000000000000 2005-01-01 5.80000000000000000 2006-01-01 8.44000000000000000 2007-01-01 10.62000000000000000 2008-01-01 3.35000000000000000 2009-01-01 5.28000000000000000 2010-01-01 5.34000000000000000 2011-01-01 3.49000000000000000 2012-01-01 5.37000000000000000 2013-01-01 5.63000000000000000 2014-01-01 6.27000000000000000 2015-01-01 6.76000000000000000 2016-01-01 6.30000000000000000