As soon as I shift the property of AMT to not Show, It starts asking me for value of AMT
I'm presuming AMT is a field. If you don't elect to show it, you're not returning it thus you can't use it. You can elect to not show fields by unchecking the show box and still use the field to apply criteria to the results. But if you expect to use a field in a calculation, you have to return it. If you are following other advice, you were likely told to use forms along with your queries, in which case, you return whatever values are needed for the calculations and either perform the calculations on forms in unbound textboxes, or if in queries, you return the value to the form based on that query but don't show it on the form. Not sure you should be storing the calculations either.
The more we hear silence, the more we begin to think about our value in this universe.
Paraphrase of Professor Brian Cox.