2005

7.1

1964

7.1

2001

7.2

2002

6.7

1932

7.3

1983

7.3

1995

7.2

2006

7.0

2002

6.9

1992

6.9

1997

6.5

2001

6.1

2001

7.5

1989

6.9

1976

7.6

2002

5.0

2005

6.9

2008

6.6

1972

7.8

1939

7.6