1986

5.6

1980

5.6

1980

6.4

1989

5.7

2008

8.3

1983

4.8

2000

6.3

1996

3.3

2008

6.0

1993

6.5

1984

5.8

1991

7.0

1996

5.7

2010

3.5

2000

6.8

1979

4.8

1991

3.3