1983

8.0

1961

6.5

2009

6.9

1946

6.7

2010

4.4

1970

6.2

1960

6.7

2001

6.8

1988

6.3

2004

6.4

1996

7.1

2005

6.2

2006

6.2

2002

6.7

2002

6.1

2004

7.1

2003

7.3

1970

7.6

1998

6.2

2006

6.5