1980

6.4

2002

6.2

1974

6.6

1965

7.7

1969

6.9

1972

7.1

1953

6.8

1981

6.8

2002

6.5

1985

7.0

1983

6.4

1992

6.0

1966

7.5

1973

7.3

1977

6.7

1979

6.3

1967

7.1

1986

6.6

1985

6.8

1991

7.2