1991

5.9

2011

6.5

1985

6.1

1971

6.4

2005

6.3

2016

4.2

2001

6.4

1946

7.5

2007

6.9

1974

6.5

1975

7.3

1977

6.7

2003

5.8

2000

5.5

1989

7.3

2016

6.8

2012

8.2

1976

6.7

1998

7.1

1969

6.8