Year	Percent
1980-01-01	7.625369999999999
1981-01-01	7.657089999999999
1982-01-01	8.603870000000000
1983-01-01	8.165310000000000
1984-01-01	9.163660000000000
1985-01-01	9.330919999999999
1986-01-01	10.258000000000000
1987-01-01	10.546500000000000
1988-01-01	10.867600000000000
1989-01-01	8.813620000000000
1990-01-01	10.634900000000000
1991-01-01	10.875900000000000
1992-01-01	14.191200000000000
1993-01-01	14.507000000000000
1994-01-01	13.955800000000000
1995-01-01	15.802200000000000
1996-01-01	18.970700000000000
1997-01-01	19.169400000000000
1998-01-01	15.992900000000000
1999-01-01	14.567000000000000
2000-01-01	17.152800000000000
2001-01-01	18.879500000000000
2002-01-01	21.316100000000000
2003-01-01	23.944700000000000
2004-01-01	24.669400000000000
2005-01-01	22.124500000000000
2006-01-01	18.006200000000000
2007-01-01	18.836700000000000
2008-01-01	19.541100000000000
2009-01-01	20.411900000000000