1985

7.5

1999

6.0

1982

5.9

1974

6.2

1990

8.5

1991

6.5

2001

7.1

1989

7.1

1992

5.7

1975

5.2

1971

4.9

1982

7.8

1995

6.0

1970

6.3

1972

5.8

1987

2.7