Variations can be a little tricky! When a product has variations, there are actually two ways Jungle Scout estimates their sales and revenue.
For those products whose variations have their own Best Seller Rank (BSR)
We estimate that item's sales independently of the other variations' sales. To see those variations, and their individual estimates, you have to go directly to the product's listing.
The variations will be represented by an indented arrow to the left of each variation's title:
For those products whose variations all have the same BSR
Because Amazon gives no indication of how those items sell differently from one another, we can't calculate the estimated sales and revenue for the variations.
In cases like this, we display the estimated sales for the product's entire listing on the top line, for the item's parent ASIN:
As for the variations of the product, those will have a '--v' in their sales and revenue columns. If you hover over that '--v' a tooltip will appear, explaining why there is no data populating for the item: