1955

7.5

2004

5.9

2006

6.6

1996

5.5

2005

6.7

1940

0.0

1996

6.0

1989

6.8

2001

6.2

2006

4.0

1991

6.6

2008

7.2

1999

6.5

2000

6.4

1973

6.9

1970

5.6

2005

5.6

1999

7.4

1954

7.9

1997

5.8