1992

7.6

2000

8.0

1991

7.9

1986

7.1

2002

3.7

1997

7.5

1994

0.0

2002

6.0

1993

5.5

1986

5.5

2004

4.5

1979

6.7

1979

6.2

1971

0.0

1979

5.7

1988

7.0

1975

7.7

2003

2.3