1961

7.7

1976

6.5

1971

7.2

1999

7.2

2006

7.1

2007

6.9

2000

7.4

1953

8.0

1955

7.5

1983

7.2

1930

7.3

1986

7.9

1972

8.7

1974

8.6

1971

7.5

2005

6.7

1952

6.8

1964

0.0

2014

7.4

1988

6.5