1970

5.5

1993

6.6

2007

6.7

2018

6.7

1987

7.9

2017

5.4

2020

6.9

1993

6.4

2009

5.8

2000

6.7

1998

7.7

2006

6.9

2002

6.5

2003

6.7

1997

5.4

2003

6.4

1961

7.2

1950

7.0

2008

6.7

1951

7.2