Year	Percent
1999-01-01	3.59754268725434
2000-01-01	3.37398270001529
2001-01-01	3.01183572757878
2002-01-01	2.92217726894762
2003-01-01	2.93283762319711
2004-01-01	2.90749742213308
2005-01-01	3.38296019866557
2006-01-01	3.50833917477511
2007-01-01	3.50032965673212
2008-01-01	3.72353446751314
2009-01-01	5.00109063123968
2010-01-01	5.66882003328572
2011-01-01	5.43564134642451
2012-01-01	5.65222938091712
2013-01-01	5.24254864854715