1990

6.9

2006

8.4

1995

7.0

2016

7.9

1992

6.8

2021

8.3

2014

7.8

1968

7.3

2016

8.0

2019

8.5

2013

8.7

2018

8.5

2017

7.0

2015

7.9

2019

8.3

1997

8.0

1990

7.4

2009

7.2

2020

7.9

2021

7.4