1932

7.5

1976

7.7

2000

7.0

2005

6.5

1968

7.2

1987

7.3

1989

7.0

1992

6.7

1998

6.6

1975

7.8

2002

7.2

1971

7.5

2003

7.8

1972

7.1

1997

7.7

1990

7.7

1997

7.4

1986

7.9

2003

5.8

1966

7.4