I have two tables I keep track Phone cards. One table has the list of all inventory (SerialNo, BookNo, QtyinBook, FaceValue and DeliveryDate) also I have another table where I keep track daily sales and I have form st up to enter daily sales (SaleDate, SerialNo, BookNo, FaceValue CardNo, BookSettled, and BookActive) BookSettled and BookActive are Yes and No. I want the BookSettled autonaticaly change to Yes from no when the CardNo reaches the last card in the book. For example BookNo 123XX has QtyinBook 50 so when the sale of this reaches 50 I want the BookSettled to swithc Yes.