1985

7.4

1994

4.3

1984

5.7

1997

6.1

1994

6.2

1994

7.8

1993

7.7

2012

6.0

2005

8.2

2002

6.5

1992

6.7

1981

6.5

1994

6.0

1988

7.8

1989

8.3

1988

3.2

1987

3.2