The Certificate of Analysis of hMNC contains the percentages of the main cell types (lymphocytes, monocytes, ...). How does PromoCell determine that these are monocytes?

Our MNC lots are checked for the rate of lymphocytes, monocytes and granulocytes w/o staining by FSC/SSC using a flow cytometer. A sample plot is attached. For our purified CD14⁺ monocytes we additionally perform a CD14⁺ staining.