1996

6.4

1978

0.0

1997

7.2

1976

4.0

1971

8.1

1978

6.7

2002

7.7

1994

7.8

1981

5.6

1980

5.0

1977

6.2

2006

4.4

1985

7.7

1985

7.5

1995

7.8

2009

5.9

1993

7.9

1978

6.7