1995

7.6

1985

7.7

2005

6.5

1982

7.9

1988

7.9

1997

7.6

1972

6.4

1999

7.4

1983

7.3

1984

6.2

1990

7.3

1987

6.5

2001

5.8

1968

7.6

1971

8.2

1984

7.7

1991

7.3

1995

7.2

1976

6.5

1999

7.1