1973

7.0

1934

4.1

1962

6.0

1990

7.7

1966

7.1

1999

7.1

2006

5.8

2001

6.0

2001

7.3

2002

6.2

1960

7.2

2004

6.9

1975

6.9

2006

6.1

1970

7.5

1998

7.2

2001

6.8

2000

6.5

1994

6.7

2007

6.7