1994

8.5

1980

8.2

1950

5.7

2000

6.3

1953

6.9

1962

7.3

1998

6.6

2006

5.3

2003

5.8

1958

7.8

1960

8.4

2006

6.6

1954

8.0

1968

7.3

1991

7.5

2000

5.9

2002

6.9

2000

7.1

1955

7.3

1999

6.5