1981

6.4

1982

7.6

2011

5.9

1997

6.5

1942

10.0

1956

5.6

2004

6.7

1990

7.8

2003

6.7

1970

7.5

2009

4.5

2000

7.1

1952

6.7

1980

6.8

1996

7.3

2003

5.1

2001

7.6

2000

6.7

2001

5.6

1989

0.0