We notice that we have transactions still with old unit costs, after we have 
updated item costs as part of year end.  What is the correct way to have 
these tranasctions update unit cost to the new cost? example - we create 
invoice when unit cost was 10.00 then at year end we recost the item to 
12.00.  we post the item after year end and the invoice still shows 10.00. 
Our receivables account picks up the 2.00 difference.