2011

5.9

1997

5.2

2005

5.5

1998

4.0

2014

5.9

1995

6.9

1987

7.7

2012

6.3

1981

4.7

1996

6.6

2006

5.2

1992

6.7

1999

3.3

1998

6.0

1989

7.4

1997

5.6

1995

6.5

2004

7.0

1981

6.9

1988

8.3

1991

6.0

1995

7.1

1992

7.5