1977

6.8

1940

6.3

1967

6.6

1988

6.4

2008

6.5

1999

4.5

1981

6.3

2014

4.6

2012

8.2

1986

6.8

1995

5.6

2010

5.7

2013

5.7

1959

6.1

2012

7.2

2017

4.8

2011

6.9

2016

8.0

2003

7.0

1998

8.6