A report is not a screenshot of a dashboard. Its job is to let someone who was not in the campaign decide what to do next month, and that takes five specific things.
Delivery against the plan
Start with what the plan said would be delivered and what was actually delivered, per placement. Averages hide the useful information: one placement at double its target and three at half is a different situation from everything landing exactly on plan, even though the totals match.
Where the money went
Media spend and management fees should be separated, and media spend should be attributed to placements. If a report gives one blended cost figure, the question 'which placement is worth keeping' cannot be answered from it.
What was changed, and when
Pacing adjustments, creative rotations and paused placements belong in the report with dates. This is the section that turns a report into a record: it explains why delivery moved, and it lets you disagree with a decision at the time rather than months later.
What the numbers cannot tell you
Impressions and clicks describe delivery, not persuasion. If the campaign's goal was sales, the report should say which part of the result the advertising can account for and which part it cannot, including anything that happened elsewhere: a price change, a stock-out, a site outage.
A recommendation with a number attached
End with what to do next, stated concretely: move this budget, drop that placement, test this offer. A recommendation without an amount or a placement is a sentiment, and sentiments cannot be approved or rejected.
Watch for these two patterns
A report that is all success metrics and no spend is usually avoiding a cost conversation. A report that always concludes 'increase the budget' is not analysing, it is upselling. Neither is necessarily dishonest, but both are easier to spot when the report states delivery against plan, money by placement and changes with dates.