1949

6.9

1968

7.1

1986

6.4

2012

6.3

2002

7.0

1957

8.1

2010

4.6

2004

5.9

2009

7.0

1943

8.2

2013

7.5

1994

6.6

2013

7.6

1979

7.1

2009

5.6

2011

7.4

2004

6.7

1986

7.3

1977

7.6

2014

4.6