2004

7.1

1997

8.4

2002

6.8

1991

7.4

2006

7.7

2003

7.5

1994

8.5

2007

6.9

2007

7.2

1991

8.0

1997

6.5

2017

6.0

2011

7.2

1991

4.2

2008

6.7

1977

8.0

1993

0.0

1974

0.0

2011

8.0

2015

6.0