1992

1.0

1997

7.2

1993

5.8

2004

7.9

1995

2.0

1994

7.8

2006

7.5

1995

7.3

1992

5.9

1988

4.0

2001

8.0

1995

5.6

1995

6.5

1999

8.3

2004

7.8

2005

7.5

1998

6.8

2002

7.3