1980

6.1

1979

6.0

1987

6.5

1985

0.0

1990

6.4

1994

7.8

1968

7.1

1984

7.2

1978

5.3

1973

6.9

1986

4.2

1986

4.4

1987

7.0

1986

4.2

1989

9.0