1990

7.4

1999

8.4

1939

7.5

1955

7.3

1986

8.0

1957

8.5

2000

8.0

2006

7.8

1992

8.1

1991

5.9

1952

7.7

1995

8.2

1967

6.8

1925

7.6

1992

7.8

1994

8.7

1969

7.1

1973

7.8

2003

6.1

1966

8.5