2014

5.6

2009

7.0

2010

6.2

1991

7.7

1997

7.4

1973

6.3

1973

7.4

2009

7.2

2008

5.7

2004

6.1

2015

6.4

2008

6.4

2004

8.1

2004

7.2

2004

6.6

1995

7.3

2012

6.5

1962

7.6

1982

7.5

2005

5.6