1983

6.3

1971

7.5

1998

7.8

1991

8.3

2009

8.0

1984

7.3

1983

6.1

1969

6.6

1984

7.7

1979

7.3

1966

8.5

2003

6.2

1999

6.3

2003

6.1

1986

8.0

1998

7.0

2010

6.3

1950

8.1

2006

6.7

1967

5.3