1987

6.4

2011

6.5

1984

5.7

1992

6.8

2023

6.7

2014

8.5

2018

7.5

2019

7.7

2017

6.7

2019

8.1

2009

7.6

2016

7.9

2018

6.9

2018

8.2

2015

7.5

2015

7.3

2017

7.6

2018

6.8

2020

8.1

2016

7.6