2015

7.3

2014

8.5

2009

7.6

1997

7.9

2012

7.2

1994

8.7

2014

7.8

2006

7.4

1999

8.0

2004

8.4

2014

7.7

2017

8.2

2005

6.9

2016

6.5

2003

7.8

2011

7.3

2006

6.6

1994

8.3

1994

8.5

1941

7.0