1957

5.0

1997

6.9

1999

6.8

1966

8.1

1981

7.4

1998

6.6

1945

7.7

1993

5.5

1939

7.6

1994

7.0

2005

6.7

2006

6.0

2006

7.1

2007

6.1

1999

7.7

2003

7.2

2001

6.7

2006

6.2

2014

5.1

2005

4.9