Year	Percent
1998-01-01	5.08779302932869
1999-01-01	7.37139012073993
2000-01-01	7.43863074590998
2001-01-01	6.80670853054207
2002-01-01	5.94341124236493
2003-01-01	6.15573995364039
2004-01-01	7.06615245060280
2005-01-01	6.45614859388610
2006-01-01	5.81470697064242
2007-01-01	4.22442476147825
2008-01-01	3.46010685062004
2009-01-01	5.84488682469681
2010-01-01	6.38386726514208
2011-01-01	5.79839778084522
2012-01-01	6.02356785492479
2013-01-01	5.90280941706410
2014-01-01	5.09984767259352
2015-01-01	4.23317747176092
2016-01-01	3.37969333088681
2017-01-01	2.33803677924514