I don't see anything other than what borisz said and you might want to change the regular expression in your substitution to be a little more strict

$returned_param =~ s/\d//g;          # what you have now
$returned_param =~ s/\d+$//;         # what I think you might want ins
+tead
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Mine only gets rid of a run of digits at the end rather than those that may appear in the middle of the name. This mayn't be a problem with your data set, but a good programmer is a paranoid programmer :-)