Year	Percent
1999-01-01	15.70546452554700
2000-01-01	13.91962653577310
2001-01-01	10.54964785753700
2002-01-01	11.44908120372840
2003-01-01	11.48588097212530
2004-01-01	10.96565410917870
2005-01-01	9.15137830012781
2006-01-01	8.45468223613499
2007-01-01	8.23197866872685
2008-01-01	11.24429947401270
2009-01-01	17.85730966974990
2010-01-01	19.85979564294650
2011-01-01	21.39048383142280
2012-01-01	24.78814551037660
2013-01-01	26.09189676616830
2014-01-01	24.44284144352510
2015-01-01	22.05655511160620
2016-01-01	19.63387923169790
2017-01-01	17.22488523770330