1981

0.0

1997

6.4

1997

6.5

1999

5.6

1998

6.5

1985

6.6

1982

0.0

1999

6.8

2004

7.5

2000

6.8

2000

10.0

1978

2.5

1976

6.4

1909

5.0

1967

7.3

1994

6.7

1992

7.4

2011

5.9

1982

6.8

2005

7.2