1970

5.5

1978

6.7

2006

5.7

2013

7.3

2013

6.9

2014

6.5

1991

10.0

1981

6.4

1933

6.6

2004

5.8

1969

6.3

1964

5.6

2014

6.0

1984

7.1

1980

0.0

2012

5.7

2008

6.5

2013

7.5

1967

6.2

2002

6.9