1937

5.0

1975

5.8

1999

5.8

2009

6.8

1973

7.5

1991

6.9

2008

6.4

1993

7.9

1948

8.2

2001

7.1

2001

6.0

0.0

2005

6.5

2008

6.1

2002

5.3

1945

8.1

1999

7.3

1991

7.6

1939

6.0

2007

0.0