1976

7.4

1980

7.0

1983

6.0

1993

2.0

1983

0.0

1991

5.3

1992

6.0

2005

6.5

2005

7.8

1990

7.5

2000

6.0

1990

0.0

2003

5.7

1981

7.8

1993

5.0