1987

4.0

1990

6.5

1984

6.3

2001

0.0

1984

7.4

2005

8.2

1985

7.7

2004

5.5

1990

8.3

2000

7.7

2004

10.0

1960

4.1

2005

7.5

1995

6.1

2004

7.3

2005

7.9

1979

6.8

2007

6.7

2001

7.6

1997

7.0