1993

6.1

6.3

2012

6.4

2014

6.8

1968

6.9

2017

6.0

2021

7.7

2007

7.0

2019

6.3

2012

9.7

2010

7.9

2015

5.9

2015

7.4

2013

7.5

2009

6.1

2017

6.7

2001

6.9

1972

6.4

2009

6.7