2014

6.8

2010

5.6

1988

6.2

2007

6.5

2013

6.2

2013

6.3

2003

6.6

2013

5.3

1993

4.8

2006

4.6

2001

4.9

1967

6.1

1975

6.8

2015

6.1

1993

5.4

2016

6.7

1949

6.2

2009

7.1

2008

6.2

1911

6.6