Serialized Inventory Item > Specific vs. Average Costing Method

Here's the difference between Specific and Average Costing Methods when calculating cost of a Serialized Inventory Item:

Specific - this refers to the exact cost of a serial or lot number entered in the system.
Average (weighted-average method) - is calculated as the total inventory value divided by the total quantities on hand during a specific date range.

To illustrate, let's say we have the following transactions for Serial Item A: 
Date | Transaction | Serial Number | Quantity  | Cost
3/1/2018 | Inventory Adjustment #1 | Serial 001 | 1 | $5 
3/1/2018 | Inventory Adjustment #2 | Serial 002 | 1 | $20 

If on 3/2/2018, the user enters an Item Fulfillment for Serial 001, the cost should be recognized at:
Specific - $5, because this is the exact cost of the serial number when it got into inventory.
Average - $12.5, because this is the Average Cost (Total Inventory Value of $25 divided by 2 Quantities) of the item as of 3/2/2018.