1997

6.0

1970

7.1

1986

6.1

1988

6.2

2003

6.0

2017

5.0

2002

6.8

2005

5.3

2014

6.7

2001

7.3

1996

6.5

1964

7.1

2007

4.0

2006

4.0

2009

6.6

1994

7.5

2010

3.6

2021

7.0

1996

5.7

2020

6.4