Variations in Stock

One of the greatest problems in achieving stock control on a computer is the control of inaccuracies. In most cases the reason for failure of a computer system to meet a customers need is that the source of stock variations is not identifiable. Following are some of the common conspirators against stock control:

• Wrong product code used on documents.

• Stock disposed of without being recorded.

• Items delivered on customer Orders without a Sales document.

• Stock credited but not returned to stock.

• Stock received but not entered on a Purchase order.

• Stock transferred to another branch without a Transfer document.

• Stock returned to supplier without a return document.

• Undocumented stock movements.

You will note that except for undocumented shrinkages, all the other causes mentioned above have to do with data entry and not business procedure. The lesson here is expect users to make mistakes. You can minimise this with training and good policies but there will always be mistakes. Accept these mistakes and move on to how to deal with them.

Most of these inaccuracies can be detected with the use of the stocktake variation report and with the stock inquiry facility. For example, stock sold under the wrong product code can be detected by finding a positive variation in one product followed by a negative variation of a similar quantity in another product which has a similar description. Credit notes for goods not fit for resale should be returned on an adjustment Credit note so as not to return the stock to on hand. Where this has not occurred you may find a positive variation (ie. book value lower than count) and a low or negative sales figure. Branch transfers that were not processed can be detected by finding a counter balancing positive and negative variation for the same product across two or more branches.