1975

8.0

1998

7.5

2018

8.3

2022

8.4

2019

7.4

2020

8.3

2019

6.9

2016

7.1

2008

7.8

2020

8.4

2013

7.7

2012

8.1

2021

8.5

2008

7.7

2017

7.9

2023

7.8

2001

7.9

2013

7.8

2003

7.6

2005

8.1