Year	Percent
1982-01-01	2.9
1983-01-01	3.4
1984-01-01	3.0
1985-01-01	2.9
1986-01-01	2.6
1987-01-01	2.5
1988-01-01	2.0
1989-01-01	1.8
1990-01-01	1.7
1991-01-01	1.6
1992-01-01	2.1
1993-01-01	2.6
1994-01-01	3.2
1995-01-01	2.9
1996-01-01	2.9
1997-01-01	2.7
1998-01-01	2.7
1999-01-01	2.4
2000-01-01	2.2
2001-01-01	1.9
2002-01-01	2.6
2003-01-01	3.8
2004-01-01	4.9
2005-01-01	4.6
2006-01-01	4.6
2007-01-01	4.2
2008-01-01	4.9
2009-01-01	5.2
2010-01-01	4.6
2011-01-01	4.8