1995

6.5

1971

6.4

1976

6.6

1972

5.6

1968

6.3

1978

6.0

1981

7.6

1982

5.8

1980

6.4

1967

6.9

1989

7.0

1992

6.7

1968

5.6

1978

4.5

1979

6.0

1979

5.0

1998

6.2

1965

7.2

1975

7.2

1985

6.9

1963

7.2

1977

4.8

1984

0.0