2017

5.9

2011

5.6

2007

5.7

5.3

1993

5.6

2003

5.4

1992

6.3

1976

5.6

2021

6.7

1994

4.6

1973

7.5

2009

4.7

2008

5.5

2010

7.7

1974

6.3

2012

8.0

2011

8.0

2014

6.2

2015

5.9

2021

6.2