There are two ways adjusted cost records can be created. The first is for linked portfolios, where the brokerage house or Yodlee sends an cost update record following a buy transaction. For example, if Yodlee provided a different holding cost but the quantity stayed the same. As the update may not occur on the same day, and/or it may apply to multiple purchase lots, the adjustment is maintained as a separate transaction record.
The second way an adjusted cost record can occur is by a user manually adjusting the cost of a past transaction without changing the share quantity. This will create an adjusted cost record that reflects the change made to the cost.