You will need to round. Anything under 50 cents rounds down to zero, so you can leave those entries blank. 50-99 cents will round up to one dollar.
**Mark the post that answers your question by clicking on "Mark as Best Answer"
You can either bypass/ignore the error (leaves the checkbox checked and 0 as the amount) or you can uncheck the checkbox and delete the value in the box (leaving it blank). The first choice is more correct, but since this is just a worksheet that rolls up into another form, those two choices should produce the same result.