Amount of business seen in a pie shop? (8)

I believe the answer is:

turnover

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'amount of business' is the definition.
(I've seen this before)

I cannot understand how the rest of the clue works.

(Other definitions for turnover that I've seen before include "Total sales or rate of replenishment" , "Business - reversal" , "Tart" , "Gross value of sales" , "Pastry; money taken by business" .)

I've seen this clue in The Times.

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