KPI tile overviews
The headline tiles at the top of a profit report are deliberately the least processed numbers on the page: totals before anything is subtracted or attributed. They are there to anchor everything below them, so that when a ratio looks wrong you can see immediately whether the cause is the numerator or the denominator.
Gross sales
Your total sales for this period, before fees, cost of goods, ad spend, and refunds are subtracted.
Ad spend
What you spent on advertising this period, before it comes off net profit. It sits on the marketplace's ad day, not your timezone.