1968

0.0

1981

0.0

1968

0.0

2000

6.5

1972

6.9

1990

7.3

1980

6.3

1950

7.7

1961

4.0

1978

6.6

1931

5.6

1981

10.0

1933

6.0

1941

7.3

1967

8.0

1969

0.0

1973

0.0

1983

6.0

1987

6.4

2008

7.0