1991

8.1

1979

7.0

2000

7.6

2009

8.0

2015

7.5

2014

8.6

2016

7.2

2019

8.3

2010

6.9

1963

7.8

1993

5.6

2014

7.3

2018

7.4

2024

7.2

2014

8.5

2021

7.7

1976

7.0

2008

7.6

2002

7.1

2017

8.3