1997

7.2

1997

5.4

1994

7.8

1984

4.0

2005

8.2

1993

6.9

2003

6.7

2005

7.5

2004

5.0

1986

6.1

1995

7.2

2007

3.5

1986

6.6

1989

8.3

1988

6.6

1993

7.1

1995

4.5

1996

6.8

1990

3.0

2001

6.3

1998

7.1

2009

5.7

1976

4.0

1987

4.6

1986

5.3

1986

5.5

1986

5.8