Procurement type E,F,X for MTO

Hello

We have use a cost sheet for MTO scenario.

The format is

Cost of Production Value is 1000

Add Prd OH on COP 10% 100

Add Admin & Marketing 5%on COP 50

Total Cost of Goods Sold is 1150

Our client requirement, the value have to be showing/ post for COP Rs 1100 & for COGS should be 1150.

In our system have showing correctly for COGS but COP have showing same as COGS when we have set E or F for field Procurement type TAB MRP2 in FG material master.

When we have set X for Procurement type then system have showing / post correct value i.e Rs. 1100.

Pls note that all FG materials are setting E for Procurement type.

My query, what is the difference between X, E and F.

Regards

Avijit