2017

6.8

2013

7.5

1985

5.3

1986

6.6

1995

5.6

1980

5.8

1970

7.0

1988

7.3

1975

7.7

1977

7.4

1954

8.1

1961

7.8

1988

5.5

1985

6.2

1996

6.9

2002

5.5

1967

6.5

1961

7.7

1990

7.3

1956

7.1