1980

6.0

1991

8.3

1994

8.7

2003

6.5

1984

8.4

2003

7.7

2014

6.1

1959

7.8

1996

8.0

1995

6.6

1975

1.0

2007

7.5

1996

7.7

2007

7.9

1978

5.9

1960

7.2

2014

6.1

1961

7.3

1963

7.0

1964

7.0