2007

7.1

2009

6.2

2017

6.8

2016

7.3

2003

8.1

2005

4.7

2006

7.4

1999

7.2

1967

6.8

1986

5.6

2006

6.6

1980

6.7

2016

6.5

2014

6.4

2012

7.9

1928

8.0

1959

6.1

1953

5.4

1998

6.5

2015

7.3