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Part 5 of 7 · Budget variance reporter series ~5 min read

How the variance report reads

Everything else in this system exists so that this page can be short. A variance report that fits on a screen, has reasons attached, and can be read in ninety seconds is a different object from a management accounts pack, and it gets used differently.

Key takeaways

  • One page. Four lines is typical, seven is a bad month, twelve means the thresholds are wrong.
  • Each line: the number, the year-to-date position, and the transactions behind it.
  • The most interesting line is the one with no single transaction behind it.
  • Filtered variances are listed at the bottom in one line each, with reasons.
  • The report is regenerable and a restated period says so at the top.

What the page looks like

July 2026 — four lines

  • Repairs & maintenance — £2,400 over (£6,400 v £4,000). Year to date £1,900 over. One invoice: Ashford Plant, £2,150, compressor repair unit 2.
  • Fuel — £1,180 over (11%). Year to date £3,900 over. No single transaction — 34 fuel card entries, average up 9% on last quarter. Third consecutive month.
  • Subcontractors — £4,200 under. Year to date £600 over. Two suppliers who invoice monthly have not this month, worth about £5,100 between them.
  • Card fees — £310 over on a rate basis. Budgeted 1.4% of card sales; actual 1.62%. Volume is on budget; the rate moved.
  • Filtered as timing: insurance (paid July, budgeted August), rates (quarterly instalment landed), stationery (YTD within 3%), accruals reversal on wages, three others — listed below.

Four lines, each with its number, its year-to-date position, and its explanation. The third one is included even though the filter would have removed it, because it illustrates the point: subcontractors is under for the month and over for the year, which is a fact worth one sentence rather than an omission.

The line with no transaction behind it

Fuel is the interesting one and the report says so with the italic note. A variance explained by one large invoice is an event: it happened, somebody decided it, and it will not recur. A variance made of thirty-four small transactions with no single cause is a rate change, and rate changes compound.

How a real variance is explained from its transactionsA vertical chain of four steps entered by a box labelled A real variance, over threshold and not filtered as timing. Step one pulls the transactions for that line in that period from the imported rows. Step two asks whether one dominant item accounts for over half the variance; if so it exits to Name it, which is an event rather than a trend. Step three asks whether the variance is spread across many transactions with no single cause; if so it exits to Flag a rate change, comparing with the prior quarter. Step four handles a few mid-sized items by listing the top three. A note says an event is a decision somebody made and a rate change is one nobody made.AWS ACCOUNTA real varianceover threshold, not timingPull the transactionsthis line, this periodTransaction rowsthe imported periodOne dominant item?over half the varianceName itan event, not a trendyesSpread across many?no single causeFlag a rate changecompare with last quarteryesA few mid-sized itemslist the top threeAn event is a decision somebody made. A rate change is one nobody made.
Fig 1. How a real variance gets its explanation. The distinction between an event and a rate change is the most useful thing the report says, and it comes straight from the shape of the transactions.
  • App integration
  • Management
  • Analytics

How many lines is right

  • Three or four is a healthy month and is what the thresholds should be tuned to produce.
  • Seven or eight is a genuinely eventful month, and the report will be read carefully because it is unusual.
  • Twelve or more, repeatedly, means the thresholds are too tight or the budget shaping has not been done. Fix the inputs rather than reading a longer report.
  • Zero, repeatedly, is worse than twelve. It means the thresholds are so loose that a real problem would pass through, and the report is decorative.

Restatements at the top

A report for a period that has been restated says so in its first line, with the date of the original and a note of which lines changed. Without that, two versions of July circulate and the person reading the second one has no way to know it supersedes the first, which is a reliable way to have a meeting about the wrong numbers.

What the report is not for

Deliberately absent

  • A forecast. This report describes what happened; extrapolating from it is a separate exercise with different assumptions.
  • Any commentary on whether a variance is acceptable. That is management’s judgement and the system has no business supplying it.
  • Departmental or per-person attribution. Account codes are not people, and a variance report that names individuals stops being read honestly.
  • A running total of variances. Summing overspends and underspends produces a number that means nothing and looks meaningful.

Next: what all of this costs to run.

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