1980

5.9

2011

6.6

1994

6.2

2016

6.1

1993

6.6

2003

6.8

1988

6.4

2009

7.3

2012

5.4

2007

7.4

1975

6.8

2006

6.1

2019

6.5

2010

5.8

1978

5.9

2020

6.9

2006

5.1

1998

6.0

1956

7.1

2020

6.7