What it means
The word comes from the old meaning of casting, which is adding up a column of figures. An undercast happens when the addition is wrong, a number is left out or a figure is entered with a missing digit.
The result is a total that does not equal the sum of the items it is supposed to represent. Auditors look for cast errors because they can hide in plain sight.
A schedule that looks tidy may have a wrong total, and if the total feeds into financial statements, the mistake spreads. For example, an undercast trade receivables list understates the amount customers owe.
The size of the error and its direction both matter. An undercast of revenue lowers reported income, while an undercast of expenses raises profit.
Even a small mistake can matter if it changes a covenant ratio or moves a result across a threshold, such as the profit required for a bonus. Spreadsheets reduce but do not remove the risk.
A formula that sums a range can leave out new rows added below it, or a number stored as text can be ignored by the sum. A simple control is to compare the total with an independent calculation, such as the control account in the ledger.
The term is used in trade and forecasting too. A sales forecast that comes in below the final result may be called an undercast, which suggests the analyst was too cautious.
Understanding which meaning applies helps in discussions between finance and other teams. The corrective entry depends on where the error sits.
If the mistake is in a supporting schedule only, fixing the schedule may be enough, but if it has flowed into the ledger, a journal entry is needed to correct the account. The correction should be documented with the reason and the approver, so that later reviewers can follow what changed.
In practice
Real-world examples.
Example
An auditor re-adds a list of accrued expenses and finds it totals $312,000, while the schedule says $302,000. The $10,000 undercast means liabilities were understated in the draft accounts, and the correction reduces reported profit.
Example
A retail finance team finds that its daily sales summary leaves out one till. The monthly sales total is undercast by $18,000, which flows into the tax return until corrected. The tax adviser also checks whether any penalties or interest could apply to the understated figure.
Example
A sales director reviews a forecast prepared by her team and sees that actual orders came in 15% above the number. She calls the forecast an undercast and asks the team to look at why they were so cautious. Over several periods, a pattern of undercasting suggests the forecast method has a built-in bias.
Formula
Calculation
Undercast amount = Correct total - Reported total
A schedule of customer balances lists five invoices of $40,000, $35,000, $50,000, $28,000 and $37,000. The correct total is 40,000 + 35,000 + 50,000 + 28,000 + 37,000 = $190,000. The schedule shows a total of $184,000 because a formula missed one row. The undercast amount is 190,000 - 184,000 = $6,000, or 6,000 / 190,000 = 3.16% of the correct total.Case study
Seen in the real world.
Kestrel Distribution is an illustrative, fictional wholesaler that closed its year with a spreadsheet of inventory counts. During the audit, the reviewer re-added the schedule and found that the total was $75,000 below the sum of the lines.
The cause was a range in the total formula that stopped one row short, which was added late when a new warehouse was opened. The undercast understated inventory and overstated cost of sales by $75,000, which lowered reported profit, and which meant the first draft of the tax computation also contained a mistake.
The illustrative outcome was a corrected set of accounts and a new control. Kestrel now agrees the inventory schedule total to the stock ledger every month, and it uses a table format so that new rows are automatically included in the total. A second person now signs off the schedule, and the sign-off is stored with the working papers.
Watch out
Common mistakes.
- Assuming that a total in a spreadsheet must be right because it was calculated by a formula.
- Correcting the total without finding the cause, so the same error appears again next period.
- Forgetting to check the effect on related figures, such as tax, ratios and covenants.
Questions
People also ask.
What is the difference between undercast and overcast?
Undercast means the total is too low, and overcast means it is too high.
How do auditors find cast errors?
They re-add schedules independently, compare totals to control accounts and use software tests that recalculate the totals.
Does an undercast always reduce profit?
No, it depends on the item, because an undercast of expenses increases profit while an undercast of revenue reduces it.
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