1973

5.0

1981

5.9

1990

3.4

1976

6.0

1995

3.9

1985

6.2

1971

4.3

1974

5.9

1978

5.9

1974

6.4

1980

4.1

1987

5.2

1983

4.6

1980

0.0

1982

6.7

1984

3.8

1999

7.5