1953

7.4

2000

6.4

2007

7.2

1920

0.0

1968

6.9

1968

5.8

1985

5.5

1972

6.2

1966

5.9

1999

6.5

1987

6.4

1955

7.2

1976

7.1

1985

7.0

1979

4.8

1960

6.0

1931

5.6

1971

6.2

1975

5.3

1944

0.0