Sums showing a negative value

[SR]

I have a query calculating the sum of checked boxes of field 'A' ('letters sent') and the sum of checked boxes of field 'B' (letters received). My sum field is counting the boxes that are checked but showing the values with a negative sign in front?? How do I correct this? Also - could I create an additional field in this query to calculate the percentage% (success rate) #B's checked/#A's checked?

 

[neileg]

Just to add to Pat's post:

Yes is stored as -1 and no is stored as 0. That's why the sum is negative.

 

[SR]

Just to add to Pat's post:

Yes is stored as -1 and no is stored as 0. That's why the sum is negative.

Thank-you for your response (its taken me forever to get time to get back to this project...) - dumb question, because I am a "very limited" Access programmer... regarding the ABS function for changing my negative valued sums - where do I use this function? do I put it in the query somewhere? I would like to just format the field in my form to eliminate the negative but I don't know where to put the function/expression (my attempts have not been successful).
Thanks again - SR