2013

4.7

2012

7.2

1991

9.5

1962

5.0

1975

4.2

1989

7.9

2011

6.1

2006

8.0

2005

7.6

2006

6.0

2006

7.5

1987

7.4

1985

8.2

2010

5.8

2010

6.9