ACCA PM December 2026: Planning vs Operational Variances — Where the 10 Discussion Marks Go Missing
You can calculate every planning and operational variance perfectly and still walk away with half the marks. The split is roughly 10 marks for the numbers and 10 for the discussion — and the discussion is where PM candidates consistently fall apart.
The examiner has said this for years
Across successive PM examiner reports the same pattern shows up: performance on the calculations is described as encouraging, with many candidates scoring full marks, while the written element — explaining what the variances mean — is "less impressive". One report goes further and notes that most candidates did not know the definitions of operating and planning variances, so those attempting an answer wrote about every other variance in the appendix instead.
That is a technical knowledge failure dressed up as a writing failure. If you can't say in one sentence what a planning variance is, you can't discuss one.
The distinction, in one line each
Planning variance = the original standard was wrong. It compares the original standard to a revised, realistic standard. Nobody in operations could have done anything about it. It is the budget-setter's variance.
Operational variance = performance against a standard that was actually achievable. It compares actual results to the revised standard. This is the one the operations manager is accountable for.
The whole point of splitting them is controllability. PM is a performance management paper — the examiner's own phrasing is that if you don't know what the number means, you can't use it to assess performance. Every discussion mark hangs off that idea.
Worked example: same numbers, two answers
Original standard material price $8/kg. Revised realistic standard $9.50/kg after an industry-wide shortage. Actual price paid $9.20/kg for 4,000kg. Planning variance $6,000 adverse. Operational variance $1,200 favourable.
Scores almost nothing: "There is an adverse planning variance of $6,000 and a favourable operational variance of $1,200. The purchasing manager has therefore performed well overall despite the adverse total."
Scores the marks: "The $6,000 adverse planning variance arises because the original $8/kg standard was set before the industry-wide shortage and was never achievable. It is outside the purchasing manager's control and should not form part of their performance appraisal — it is instead evidence that the standard-setting process needs reviewing. The $1,200 favourable operational variance is the controllable element: against the realistic $9.50/kg benchmark the manager secured material 30c/kg cheaper, suggesting effective negotiation or sourcing. On a controllable basis the manager outperformed, and appraising them on the total variance alone would be demotivating."
Same two numbers. The second answer names the cause, assigns controllability, states the performance implication and points to a management action. That's four separate mark-scoring moves.
What to do
1. Write the definition into your answer. One sentence defining each variance type before you discuss it. It is free credit and it forces you onto the right track.
2. Attach every variance to a named person. Who could have influenced it? If the answer is "nobody in operations", say so explicitly — that is the point of the planning variance.
3. End every paragraph with a consequence. Revise the standard. Don't appraise on this figure. Investigate the supplier. Change the reward basis. Discussion marks reward implications, not descriptions.
The bottom line
PM pass rates have sat in the low-to-mid 40s for years, and Section C is where most candidates make or lose the paper. A 20-mark variance question where you nail the calculations and waffle the discussion is a 10/20 — not enough on its own to carry you over the line.
The numbers get you to half marks. The controllability argument gets you the pass.