1981

5.2

1987

6.8

1988

0.0

1997

5.4

1977

6.3

1998

7.3

2001

1.0

1974

6.0

1994

1.0

1993

0.0

1994

7.0

1995

0.0

1970

6.2

2002

6.0

1978

5.5

2009

6.1

1988

4.5

2010

0.0

2005

4.5

1992

3.4

1998

0.0