How do you measure/apply Stock Turn to stores that have not been open for a full year

It’s not every day that I get stumped by a GOOD question from a customer, but it’s extra fun for me:

How do you measure/apply Stock Turn to stores that have not been open for a full year (this also applies to Comp Stores that have turned Comp mid-year.)

I am used to an Annual Turn based on annual sales/avg stock, an Annualized Turn (looking back 52 weeks from the current period), a Monthly Turn.

What about Turn for a store that’s been trading for, say, 32 weeks of Last Year? How do you do them apples/to/apples numbers in that case?

How do you do it?