1996

5.8

2005

6.7

1977

7.0

1995

6.5

1984

6.8

2008

5.7

2000

7.1

1978

4.2

2005

6.1

1957

5.2

1973

6.2

1964

6.5

2007

5.2

1987

5.7

1981

6.5

1951

5.8

1977

8.2

1956

7.3

1962

6.2

1972

5.8