2001

8.3

1992

6.8

2011

7.5

2002

8.3

2009

7.7

2010

7.8

2003

7.9

2010

8.0

2008

8.5

1983

8.0

2008

8.9

2001

7.7

1998

6.8

1993

5.6

2007

7.6

2015

7.5

1987

8.3

1981

7.9

1995

6.4

2014

8.1