1961

7.3

2018

7.2

2010

7.1

2009

7.5

1956

6.3

2013

7.1

2017

7.7

2005

6.2

1994

6.7

2019

5.7

2006

6.4

1968

6.9

2016

6.1

2010

6.5

2002

6.2

1980

5.4

2008

6.7

2021

5.3

1974

6.7