Aggregation of Replacement start and Replacement end dates in History Replacement engine

Aggregation of the Replacement Start Date and Replacement End Date occurs when the History Replacement (HR) engine is run where the specified item level is higher than the cycles “Item Hierarchy level for storing scenario values”, or where the location level is higher than the lowest level of the Cycle.Module hierarchy.

During the aggregation, the engine must determine the appropriate values for the Replacement Start Date and Replacement End Date mapped measures. These parameters can be accessed from the Measure Mapping tab on the Engines screen. See, Defining a History Replacement Engine.

The replacement start date is determined as the earliest start date in the Replacement Start Date mapped measure for all base-level elements of the aggregate level. If the start date is not specified for the elements, the application uses the lowest history index, 0.

The replacement end date is determined as the latest end date in the Replacement End Date mapped measure for all base-level elements of the aggregate level. If the end date is not specified for the elements, the application uses the highest history index, which indicates the most recent history period.

Example 1

For item "Car” at location “North”, there are three base-level elements (Item X, Item Y, Item Z) with these mapped measure values:

  • Replacement Start Date:
    • Item X: 2020‑03‑01
    • Item Y: 2020‑04‑10
    • Item Z: 2020‑03‑30
  • Replacement End Date:
    • Item X: 2020‑06‑01
    • Item Y: 2020‑06‑30
    • Item Z: null

These are the aggregated values for "Car":

  • Replacement Start Date: 2020‑03‑01 (earliest start date)
  • Replacement End Date: 2020‑06‑30 (latest populated end date)

Example 2

For item “Car” at location “East”, there are three base-level elements (Item X, Item Y, Item Z) with these mapped measure values:

  • Replacement Start Date:
    • Item X: 2020‑02‑01
    • Item Y: 2020‑02‑01
    • Item Z: null
  • Replacement End Date:
    • All three items: null

For the FY20 M07 cycle period:

  • Most recent history period: FY20 M06
  • Most recent history index: 35

These are the aggregated values for “Car”:

  • Replacement Start Date: 2020‑02‑01 (earliest populated start date)
  • Replacement End Date: null → engine uses replacement end index = 35