1998

6.9

1992

6.7

2004

8.0

2002

6.5

1986

6.7

2005

6.4

2007

6.8

2002

6.3

2007

6.3

1992

5.3

1988

6.2

1988

6.2

2007

4.9

1990

6.7

1986

6.0

1994

6.2

1984

7.3

1984

6.3

2012

6.0