1961

6.9

1997

8.4

1983

7.9

2012

6.6

1956

7.1

2000

6.4

2012

7.4

2008

5.9

1978

6.8

1977

8.2

1927

7.5

1986

8.0

2007

7.5

1992

8.1

1987

6.5

1984

6.1

2002

7.3

1971

6.4

1999

6.8

1983

6.1