1979

7.1

2003

6.2

2020

6.5

1976

7.6

2003

7.5

2003

7.9

1970

7.6

1983

7.3

1982

7.6

2017

6.3

2003

7.8

1996

7.9

2003

6.8

1987

8.1

1999

8.4

1988

6.5

1967

6.1

1929

7.9

2007

6.9

1957

7.9