1984

7.8

2006

7.9

2014

6.4

2018

7.9

1963

7.8

1990

7.6

2015

8.0

2009

7.2

2016

7.5

2001

7.8

1993

7.9

2008

6.7

1971

7.6

1982

7.6

2014

8.4

1955

7.7

2015

7.9

2010

7.5

1994

7.4

2013

6.8