Year	Percent
1999-01-01	53.2609
2000-01-01	36.3934
2001-01-01	31.5932
2002-01-01	24.1471
2003-01-01	17.3803
2004-01-01	22.7593
2005-01-01	22.2534
2006-01-01	23.3795
2007-01-01	32.6442
2008-01-01	24.3083
2009-01-01	36.3215
2010-01-01	36.7201
2011-01-01	34.4274
2012-01-01	31.7714
2013-01-01	30.5133
2014-01-01	21.1821