1972

6.4

1985

7.4

1987

7.5

1982

8.2

1981

5.5

1980

6.4

1982

6.8

1982

6.8

1994

8.1

1963

6.0

1983

5.7

1982

4.3

1984

5.7

1996

5.5

1996

6.8

1984

7.2

1987

5.3

1999

6.1