1984

9.1

2006

6.8

1996

8.1

1975

6.0

2013

10.0

2013

9.2

1972

8.1

1994

9.2

2005

7.9

2000

8.2

2006

8.1

1989

7.9

2005

9.2

1995

9.7

2007

8.2

1975

8.2

2013

4.6

1966

8.3

1997

8.9

1978

7.3