1964

7.9

1976

7.0

1990

6.9

2008

8.3

2018

6.9

2016

5.8

2007

7.5

2012

6.3

2011

7.1

2008

7.4

2013

6.8

2008

7.7

2015

7.1

2006

6.9

1992

5.8

2013

7.3

2017

6.1

1969

6.7

2018

7.3

2016

8.3