2007

0.0

1996

6.7

2006

4.4

1999

6.5

1977

7.0

1994

6.6

1974

6.3

1985

6.6

1997

5.1

2003

6.2

1960

7.6

1987

7.2

1982

6.6

1997

7.6

1999

6.2

1967

6.7

1959

7.1

2001

6.3

2006

5.9

1991

6.7