1973

10.0

1975

7.1

2009

7.4

2003

6.2

2011

6.1

2006

7.8

2021

8.5

2016

7.3

1993

7.9

1966

7.2

2013

7.5

2017

7.0

2015

7.5

2008

7.6

2011

8.4

2014

7.6

2016

8.0

2007

7.7

2016

7.2

2020

6.8