1989

5.1

2001

7.5

1984

7.7

2009

6.0

2004

7.9

2011

6.7

2003

6.9

2006

6.9

1986

5.8

2010

7.1

1953

7.9

1973

6.5

2012

8.2

2008

8.0

1982

7.9

2010

6.3

2013

5.3

1971

6.4

1952

7.9

1991

6.8