1982

7.6

2001

7.5

2004

7.3

2006

8.2

1962

7.9

2006

6.9

2002

7.4

1968

4.2

1996

6.6

2008

7.6

2003

6.6

2007

6.5

1949

6.0

1999

7.0

1973

7.4

1982

6.9

1981

5.5

1989

7.5

2006

6.5

2006

5.4