I have been trying to determine the early surrender (or late surrender, doesn't matter for non tens) zen indice for 16 v 8 and 9. CVdata gives me the index of +1 for 16 v 9which makes no sense. Basic stratagy for this play is surrender so obviously the index has to be negative. Also I have got values anywhere from 15 to 9 for 16 v 8. Any comments on this?