1997

6.8

1990

6.2

1998

6.7

2007

5.6

1949

6.0

1973

6.8

2001

6.3

1999

6.8

1984

6.8

1995

6.5

1993

7.0

1972

7.1

2008

6.8

1967

5.5

1920

0.0

1951

7.7

1947

7.6

2007

6.7

1946

5.9

1975

4.0