Year Percent 1992-01-01 53.1542000000000000 1993-01-01 25.6071000000000000 1994-01-01 11.4600000000000000 1995-01-01 6.8646699999999990 1996-01-01 6.7687200000000000 1997-01-01 7.6268400000000000 1998-01-01 2.8004500000000000 1999-01-01 2.1612800000000000 2000-01-01 1.5467799999999998 2001-01-01 2.0312000000000000 2002-01-01 2.7059900000000003 2003-01-01 3.0443599999999997 2004-01-01 2.5806200000000000 2005-01-01 2.3988400000000003 2006-01-01 2.4647500000000000 2007-01-01 2.7126300000000000 2008-01-01 5.6917700000000000 2009-01-01 8.0206800000000000 2010-01-01 11.4321000000000000 2011-01-01 10.5138000000000000 2012-01-01 10.3391000000000000 2013-01-01 11.7691000000000000 2014-01-01 12.9687000000000000 2015-01-01 9.8220000000000010 2016-01-01 16.4315000000000000