I'm trying to format a column in my UltraWinGrid and seem to be stuck.  The data that is bound is a string that contains only numbers (i.e. 262546500 or 1004344131).  I would like this to be formatted with a dash before the last two numbers (i.e. 2625465-00 or 10043441-31).  Is there a way i can do this, no amount of mask formatting seems to product the effect i'm looking for

 Note that my data can be either be 9 or 10 characters long but there should always be a dash displayed before the last two characters.  I do not want the underlying data changed, only the way it's displayed. 

I have experimented using a variety of MaskInput values (even though i'm not inputting anything, only displaying) but the fact that there are either 9 or 10 characters seems to be causing a problem.  What works for a length of 9 fails for 10, and so on.  It seems as if the mask works from left to right but i'm not sure if that is the problem.