1980

8.4

2011

6.9

2004

8.4

2008

6.8

2005

6.8

2014

5.6

1999

7.1

2011

8.0

2015

7.4

1957

8.1

2009

6.6

2006

6.9

1983

7.9

2009

7.1

1956

7.7

2012

8.2

1929

7.8

2010

7.2

1995

8.2

2000

8.2