2015 6.5

1998 7.4

1997 6.9

2012 6.7

2011 6.1

2007 8.0

1964 8.3

2010 7.5

1994 6.9

1990 7.8

1961 7.3

2007 7.8

2011 7.6

2007 6.5

2004 6.8

2016 7.1

2002 7.6

2012 7.7

2011 7.8

2011 6.9