Year Percent 1995-01-01 2.062020000000000 1996-01-01 1.995200000000000 1997-01-01 2.446860000000000 1998-01-01 2.821670000000000 1999-01-01 3.310510000000000 2000-01-01 4.229430000000001 2001-01-01 5.206430000000000 2002-01-01 5.823440000000000 2003-01-01 6.375300000000000 2004-01-01 7.578689999999999 2005-01-01 8.895780000000000 2006-01-01 11.034900000000000 2007-01-01 13.778900000000000 2008-01-01 16.213500000000000 2009-01-01 18.300300000000000 2010-01-01 19.891300000000000 2011-01-01 21.788300000000000 2012-01-01 22.958200000000000 2013-01-01 26.313500000000000 2014-01-01 29.416100000000000 2015-01-01 32.524400000000000 2016-01-01 36.587100000000000