2005

6.8

2017

7.3

2014

6.2

2006

7.8

2014

7.7

2002

6.8

2014

9.1

2003

5.6

2001

7.0

2015

4.7

2011

7.1

2007

7.2

1988

5.5

1968

4.9

1900

4.9

1974

6.7

2013

7.1

2017

9.0

2017

7.0

2013

6.5