2007

5.6

2004

5.8

1998

6.7

2002

6.3

1988

6.2

2000

7.0

1937

7.9

1975

5.3

1986

6.7

1952

7.8

1981

7.5

2007

0.0

1959

7.7

1999

6.4

1979

4.8

1960

10.0

1991

6.3

1990

6.9

1987

7.5

1995

7.3