1956

7.5

1990

6.1

1952

7.7

2006

6.7

1961

7.9

2013

5.8

1998

8.1

2013

6.5

1994

8.0

1983

7.4

1975

7.8

2007

7.4

2009

7.0

2011

5.2

1988

6.3

2010

8.4

2014

7.5

1977

6.7

1988

7.4

2000

6.0