Why measured and docketed quantities disagree

A load arrives with a figure written on the paperwork. Your side measures it and gets a different figure.

This happens constantly, on every site, with every material, and the ordinary response is to treat it as either a rounding matter or an accusation. It is usually neither. The gap between the docketed quantity and the measured quantity has half a dozen ordinary causes, and knowing which one you are looking at is the difference between a conversation and a dispute.

The two numbers are answers to different questions#

The docket says what the seller loaded, measured by the seller's method, at the seller's premises, at dispatch.

Your measurement says what your side counted, by your method, at your gate, on arrival.

Written like that, it would be surprising if they always matched. Same material, two places, two times, two methods, two people, each with a reason to round in a particular direction.

The ordinary causes#

Different methods of measurement. Steel bought by weight and counted by piece. Sand ordered by volume and delivered by a lorry whose capacity is nominal. Aggregate weighed at a weighbridge against aggregate estimated from the height in the body. Each method has a tolerance and the two tolerances do not overlap neatly.

Moisture. Sand and aggregate carry water, and the amount changes with the weather and with how long the stockpile has been standing. A load weighed after rain weighs more and contains no more usable material. If one end weighs and the other counts volume, this alone will produce a persistent, seasonal, completely honest discrepancy.

Bulking. Damp sand occupies more volume than the same sand dry or saturated. A truck body that holds a certain volume holds a different mass depending on condition. Volumetric measurement of sand is unreliable for exactly this reason, and everybody knows it, and it is done anyway because it is quick.

Losses in transit. Spillage, dust, breakage in bagged material, a bag split on the tailgate. Real, small, and not usually anybody's fault.

Timing of the count. Material counted as it comes off, versus counted after it is stacked, versus counted the following morning from a heap. Each further step adds a chance to lose or double-count.

Partial delivery. One order, several vehicles. If the docket is written for the order and the arrival is one vehicle, the two figures are not comparable at all and the whole comparison is a category error.

The causes that are not ordinary#

Deliberate short delivery exists. So does a weighbridge that reads generously for a particular customer, and material sold twice.

The useful point is that you cannot tell these apart from the ordinary causes by looking at a single delivery. A one-off gap is noise. What identifies the other kind is pattern: the same vendor, the same vehicle, the same driver, the same direction of error, over time.

Which means the entire diagnostic capability depends on whether your measured quantities were recorded at all. If your goods receipt notes were written by copying the vendor's docket — as they very often are, because it is faster — then every gap is zero, the pattern cannot exist, and you have no way of knowing which of the two situations you are in.

Record the gap, do not resolve it#

The instinct when the two numbers differ is to pick one and write it down. This is the wrong move and it is nearly universal.

Both numbers are facts. The docketed quantity is a fact about what the seller says they sent. The measured quantity is a fact about what your side counted. Writing down only one of them destroys information that cannot be recovered later, and the information destroyed is precisely the information a pattern is made of.

The right shape is three fields: docketed, measured, and the difference — with a place for a reason when somebody knows one. Short by two bags, one split on tailgate is a complete and useful record, and the supplier has the same interest in it being written on his own copy at the gate — the challan that protects the supplier. Received: 98 is not, because next month nobody can tell whether it was ordered as 98 or ordered as 100.

We arrived at the same conclusion on the money side of the business, from a completely different direction. When a payment is made for less than the agreed amount, the system now asks why before it accepts, and the shortfall and its reason land on the record together. The agreed figure stays reconstructible as paid plus deducted. That story is paying less than agreed, and the principle is identical: a difference with a reason is information, and a difference silently absorbed is a number nobody can ever explain again.

Which number should stock be posted at#

The measured one. Always.

Stock is a claim about what is physically present. The docket is a claim about what was dispatched. Posting the docketed quantity into stock means your stock ledger is a copy of your vendors' dispatch notes, which is a fine record of what you were told and a poor record of what you have.

The docketed figure still matters — it is what the invoice will be based on, and reconciling those two is the entire purpose of three-way matching. But it belongs on the purchase side of the ledger, not the stock side.

What to do about a persistent gap#

1. Check the method first. Nine times in ten, a systematic gap is a systematic difference in how the two sides measure, and it is fixed by agreeing a method rather than by an argument about honesty.
2. Agree a tolerance in writing, per material. Cement in bags and sand by the lorry do not deserve the same tolerance and should not be given one.
3. Fix the measuring point. Same place, same equipment, same stage of unloading, every time. Most gaps that look like theft are two people measuring at different moments.
4. Then look at the pattern. After the first three, whatever is left is worth a conversation with the vendor, and you will have dated records to have it with.

The short version#

Two different people measured two different things at two different moments. Of course the numbers differ.

Write both down. Write the difference down. Write the reason down when there is one. The gap is not the problem; the gap with no record is.