1979

8.3

2001

7.8

2009

4.5

1961

6.9

2004

7.2

2017

7.4

2006

6.5

2007

6.2

1943

5.5

2020

6.6

1997

6.6

1996

6.0

1993

8.0

2000

6.8

1986

6.2

1975

6.1

1996

5.9

2018

6.8

1997

5.9

1994

8.0