Year	Percent
1998-01-01	47.5284942446967
1999-01-01	47.7320707504247
2000-01-01	48.1573843068812
2001-01-01	48.4606212317588
2002-01-01	48.7940298802271
2003-01-01	49.1139145353076
2004-01-01	48.9443902069071
2005-01-01	48.7293365425587
2006-01-01	49.0728780943564
2007-01-01	49.0998867262323
2008-01-01	48.7492573695286
2009-01-01	47.4722222040387
2010-01-01	46.7229481029257
2011-01-01	46.4733316729084
2012-01-01	45.7152863092788
2013-01-01	44.3929873113180