1998

7.5

1993

6.6

2005

6.3

1986

5.3

1994

7.3

1996

4.0

1978

7.2

2006

6.8

1996

8.1

1997

6.1

1988

6.3

2002

0.0

2006

7.8

1987

7.3

2004

8.0

1982

6.3

2005

8.0

2004

7.5

1976

7.0

1996

4.8