Reports on POTENTIAL, where is the "QUANTITY" field?

Reports on POTENTIAL, where is the "QUANTITY" field?

Report for POTENTIALS have access to all fields but QUANTITY.  By this, I mean the actual QUANTITY field on the LEAD.

I am in the coffee business and that field is used for number of kilograms of coffee.

I am trying to create a report that summarizes the following by CLIENT (Account Name) per MONTH:
  • AMOUNT total (Value of the sale)
  • QUATITY total (number of KGs of coffee)
  • COUNT (number of orders made during the period)
Sample from SalesForce:


Please HELP.  It is a very useful report for us.