2008

6.7

2017

5.7

1988

6.9

2006

8.2

2004

4.0

2005

10.0

1973

2.5

2004

0.0

1974

7.7

1968

6.8

2000

6.2

1972

6.7

1991

7.3

2000

4.6

1992

7.3

2007

0.0

2007

7.3

2020

6.2

2013

6.2

1997

6.2