Year	Percent
1990-01-01	16.1591
1991-01-01	14.3156
1992-01-01	13.3824
1993-01-01	12.8961
1994-01-01	11.5947
1995-01-01	12.6600
1996-01-01	13.3891
1997-01-01	15.1791
1998-01-01	17.2831
1999-01-01	14.8398
2000-01-01	15.7252
2001-01-01	15.9776
2002-01-01	17.5912
2003-01-01	19.1679
2004-01-01	19.6913
2005-01-01	18.1044
2006-01-01	18.5306
2007-01-01	20.0507
2008-01-01	20.5904
2009-01-01	23.5626
2010-01-01	20.0856
2011-01-01	20.3186
2012-01-01	19.4615
2013-01-01	22.4654