@grejon04 : it's not really advisable to backdate or predate a worksheet against existing inventory worksheet transactions. Although the system gives that capability but the downside of doing it is it causes a recalculation for the entire cost history of the item. In terms of recalculation times, the time it takes to complete and update the cost will depend on the volume of historical transactions and the nature of the items especially if serialized, it uses bins or lot numbers. I strongly recommend not to predate an existing one - it's a risky process that most NS clients encountered tons of issues on cost recalculation. Worst for some they end up quitting NetSuite cause the data in the system is no longer reliable. Fixing is also not guaranteed - I've worked with QA engineers before assigned to these kinds of stuff in NS...especially the serialized, bin and lot numbered once...it seems to be recurrent once you have the issue. That's why part of NS' move in Prod Dev side of SCM is to overhaul the cost engine of NS...not sure if this has already been rolled out completely - things they do internally that really has a big impact with the on going costing issues encountered by NS users