2009

5.7

1987

5.5

1984

6.1

1983

6.9

1994

5.8

1997

6.1

1993

6.3

1991

6.8

1994

6.7

2005

6.3

1985

6.2

2008

5.7

2006

6.5

1996

6.5

1997

5.2

2003

6.1

2002

4.3

2000

7.2

2002

7.1

2002

5.4