1999

6.4

1994

6.9

1972

7.3

1993

5.8

1998

5.6

1986

6.9

1987

6.9

1976

0.0

1990

4.6

1991

5.8

1983

6.7

1977

6.2

1988

6.7

1977

7.0

1979

7.0

1995

6.4