1997

6.5

1972

8.6

1960

5.0

1994

6.3

1980

6.8

1984

6.5

2002

7.9

1973

6.9

2013

6.8

1995

5.8

1985

7.5

1984

8.1

1969

7.0

1958

6.7

1974

7.5

2012

4.0

1975

7.5

1950

0.0

1972

0.0

1958

6.5