2003

6.0

2011

6.5

2005

7.5

2016

4.2

1979

7.3

2010

8.2

2000

5.5

1986

7.6

2007

7.4

2013

6.8

1987

7.3

2010

7.7

2008

6.7

1998

6.0

1991

5.9

2011

6.9

1988

7.8

2009

6.2

2003

5.8

2016

6.8