1953

7.2

2016

7.7

2012

6.1

2014

7.8

1980

6.8

2017

7.3

2007

6.5

2012

6.6

2013

5.9

2006

7.8

2013

6.7

1999

6.6

2012

7.7

2014

8.0

2000

5.2

2009

7.5

2017

7.4

1975

6.4

2009

6.6

1988

6.5