Year	Percent
1999-01-01	6.02464556711732
2000-01-01	5.33848411205624
2001-01-01	4.17663331696542
2002-01-01	4.65680952413228
2003-01-01	4.82652329621889
2004-01-01	4.71655295711415
2005-01-01	4.12389573189422
2006-01-01	3.68124265131346
2007-01-01	3.72229402400740
2008-01-01	5.84184205987365
2009-01-01	10.10811683117310
2010-01-01	11.11242944226480
2011-01-01	11.82851791463270
2012-01-01	13.70235010145430
2013-01-01	14.10314360622830
2014-01-01	12.88890422901500