Average days between turns on raw material

A customer we do converting for is looking to find out the average days it takes us to turn through raw product they send us to convert. I think for Lots I could easily take the min date and max date from part tran but stuff not lot tracked i’m not sure how to go about it since there aren’t single pieces identified like with our lots. (One lot is one roll of paper) Ideas?

Are raw materials received to a Job?

If so, I am wondering you couldnt search PartTran by Part\Job, you could use a similar process on the way out of the final operation too.

Are they looking for the accounting version of turns? or actual physically using something up? Accounting wise, if I have $1M in inventory and $2m of inventory flows through in a year, I have 2 turns. Even if $750k doesn’t move, and you actually use the $250k 8 times.