1997

7.2

2009

6.4

1998

1.5

1994

6.2

1996

6.8

1993

0.0

2003

8.0

1999

6.8

2001

8.0

1998

0.0

1993

6.1

1993

3.3

1991

6.1

1988

6.4

2005

4.0

1998

7.1

1985

6.3

2007

7.0

1999

8.3

2014

6.6