line items - use in workflows

in line items I have created an item that has a unit price and quantity. Hubspot will only calculate their total amount. We do business in the energy sector, the margin is important to us and not the total amount. I created an individual calculation that calculates my margin and the total volume of electricity supplied. Now I have to enter the data manually. If I could, for example, copy the quantity from line items via workflow to another properties, I can use this data in the calculation and calculate the margin automatically.