Year Percent 1995-01-01 1.6538400000000002 1996-01-01 1.5836700000000001 1997-01-01 3.4974500000000000 1998-01-01 4.7776000000000000 1999-01-01 1.7550200000000000 2000-01-01 1.2980200000000002 2001-01-01 2.2071099999999997 2002-01-01 2.8145700000000002 2003-01-01 4.6185100000000000 2004-01-01 6.5289000000000000 2005-01-01 7.7560500000000000 2006-01-01 8.5457000000000000 2007-01-01 10.9372000000000000 2008-01-01 18.1680000000000000 2009-01-01 32.3278000000000000 2010-01-01 31.6416000000000000 2011-01-01 28.5071000000000000 2012-01-01 29.8004000000000000 2013-01-01 31.9648000000000000 2014-01-01 35.3466000000000000 2015-01-01 42.0656000000000000 2016-01-01 41.2502000000000000