1968

6.9

2017

5.6

2013

6.5

2014

6.8

2012

9.7

1988

5.5

7.8

1967

6.2

2021

7.7

1993

6.1

2011

7.4

2008

5.8

2023

6.3

2009

6.7

2011

6.6

2014

5.6

2016

6.1

1984

9.2

2003

7.2

1998

6.0