Year Percent 1992-01-01 1.6134899999999999 1993-01-01 1.6637800000000000 1994-01-01 1.8555400000000002 1995-01-01 2.1189200000000000 1996-01-01 2.2474900000000000 1997-01-01 2.3686000000000000 1998-01-01 2.7712500000000000 1999-01-01 3.2081000000000000 2000-01-01 3.4379600000000000 2001-01-01 4.3036600000000000 2002-01-01 5.0501100000000000 2003-01-01 6.1372800000000005 2004-01-01 7.4729000000000000 2005-01-01 8.1264899999999990 2006-01-01 8.8526899999999990 2007-01-01 10.4810000000000000 2008-01-01 9.4844400000000000 2009-01-01 9.4067300000000000 2010-01-01 9.7901800000000000 2011-01-01 10.2829000000000000 2012-01-01 11.0023000000000000 2013-01-01 12.0524000000000000 2014-01-01 13.0837000000000000 2015-01-01 13.6816000000000000 2016-01-01 16.1846000000000000