Year	Percent
1991-01-01	17.2295
1992-01-01	16.9684
1993-01-01	25.4567
1994-01-01	31.6332
1995-01-01	33.8116
1996-01-01	28.5278
1997-01-01	24.0113
1998-01-01	24.9147
1999-01-01	25.1696
2000-01-01	21.6188
2001-01-01	18.6785
2002-01-01	15.2133
2003-01-01	13.9373
2004-01-01	14.8751
2005-01-01	16.0445
2006-01-01	23.0400
2007-01-01	23.6195
2008-01-01	22.7306
2009-01-01	28.9424
2010-01-01	26.5859
2011-01-01	25.6148
2012-01-01	28.1565
2013-01-01	31.1532
2014-01-01	27.6174
2015-01-01	28.3710
2016-01-01	25.2534