1986

5.8

1988

5.1

1982

5.7

1981

7.5

1975

6.0

1995

3.2

1978

4.8

2007

4.6

1985

7.1

1982

4.4

1975

4.5

1993

0.0

1992

4.8

1991

0.0

2002

2.0