1975

7.4

1983

2.0

1971

8.1

1992

0.0

1987

7.7

1984

7.5

1984

7.3

1993

7.0

1995

6.5

1985

3.0

1982

6.4

1985

0.0

1990

7.9

1985

7.6

1986

5.7

1988

5.7