1991

2.5

1995

3.9

1991

4.7

1987

6.5

1982

6.8

1999

8.2

1985

6.5

1993

5.4

1984

7.2

1987

7.7

2005

0.0

1994

7.0

1986

5.9

1994

6.0

1986

7.9

1999

8.2

1990

6.9