Break down sales data by product, region and rep

Sales data (pasted below or attached):
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{{data}}
"""

What the columns mean (whether amounts are before or after discounts and returns, the currency, and which date each row uses):
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{{column_notes}}
"""

Periods to compare: {{periods}}
Targets or quotas, if any: {{targets}}
Known events in the period (price changes, new reps, lost accounts, promotions): {{known_events}}
Who it is for: {{audience}}

Task: Break down this sales data by product, region and rep, and explain what is driving the change between the periods, for {{audience}}. The goal is to show what moved the total, with every figure traceable to the data.

Deliver:
1. Headline: total sales in each period and the change in amount and percent, with the calculation on one line, for example "(148,200 - 131,500) / 131,500 = 12.7%".
2. Three tables, for product, region and rep, each with the columns Name, Sales (first period), Sales (second period), Change, Change %, Share of total change, sorted by the size of the change. Check that each table's changes add up to the total change, and show the sum.
3. Drivers: where the columns allow, split the change into volume (more units or customers), price, and mix (a different blend of products). Say plainly if the data cannot support this split.
4. Concentration: how much of the change comes from the top 3 items in each table, and any single deal or customer large enough to distort the picture, with totals shown with and without it.
5. Points to discuss: up to 5 bullets, each tied to a number above.

Requirements:
- Use only the data and events above. Where an event lines up with a change, say they coincide; do not claim it caused the change.
- Compare reps against their targets where given, and note differences in territory or account mix if the data shows them. A ranking by total sales is not a judgment of anyone's performance and should not read as one; the manager draws conclusions about individuals.
- Show every percentage with its underlying amounts.
- Keep the text outside the tables under 400 words.

If the periods are uneven (for example, one has more selling days) or a column needed for a table is missing, say so before the tables. Rows with no product, region or rep go in a "Not recorded" line, counted, not dropped.