1979

6.0

1980

8.4

2008

7.6

2010

7.0

2023

6.7

2014

7.5

2012

6.2

1994

8.5

1975

7.8

2012

6.9

2002

5.5

1999

8.4

2014

7.6

2014

6.0

2017

6.8

1993

7.2

2003

5.6

2001

7.0

2005

7.5

2000

6.9