If you create a table that contains just numbers [Number] from 0 to maximum number then create an append query similar to the following:
INSERT INTO Deliveries ( SaleID, DeliveryDate, DeliveryValue, [<NoOfDeliveries] )
SELECT Sales.SaleID, DateAdd("m",[Number],[FirstDeliveryDate]) AS DeliveryDate, [SaleValue]/[NoOfDeliveries] AS DeliveryValue, Numbers.Number
FROM Sales, Numbers;
If NoOfDeliveries is not stored in the Sales table then you can still use this and be prompted.
The alternative is to use VBA to create the records using a For loop and DAO commands or just execute a built up string of SQL.