2006

6.7

1982

6.9

1988

7.3

2005

8.3

2001

7.2

1993

7.1

1994

7.8

1987

5.9

1984

4.3

1979

6.8

1987

6.3

2007

7.6

1983

6.4

1998

6.4

2001

7.0

1996

6.8

2001

7.8

2016

8.2

1981

6.0

1987

6.5

1991

6.5