2001

5.2

1977

6.7

2009

4.7

1972

4.0

2007

6.5

1967

6.6

2006

5.5

2010

7.5

2004

6.7

2009

7.5

2009

5.6

1996

7.3

1972

7.3

2005

4.7

2010

6.4

2012

6.3

2002

6.7

2014

5.6

2016

7.4

1991

7.0