Use this recurring analysis method with the freshly supplied file.
For [selected period], answer [named questions] using [definitions,
units and output grain]. Preserve valid zero and missing values.
Ask for the file, period and changed definitions if absent. Do not reuse
previous dates, totals or source facts. Show source coverage, actual
calculations and a small check case. Keep unavailable results explicit
rather than filling them with a plausible zero or last run's answer.

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Show which source records belong to the selected period and why.
Keep original units and missing convention. For every requested answer,
state its source coverage and calculation. If there are no matching
records, distinguish that from observed records with a genuine zero.
Do not claim the new file matches the old schema without inspecting it.

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The routine kept [old answer/period] after the input changed to [fact].
Correct the source and period dependency while retaining the stable
question definitions. Preserve the missing-versus-zero rule. Show the
affected record IDs and revised calculation, then repeat the small
changed-input check. Do not declare the routine tested from a static total.
