What is Level of Effort, Discrete & Apportioned Effort?
Earned value recognizes three work types: discrete effort — measurable, tied to specific deliverables (pour 100 meters, earn 100 meters' value); apportioned effort — work that scales with some discrete base (inspection earned as a fixed % of the work inspected); level of effort (LOE) — sustaining work with no deliverable (project management, site security) that earns value simply as time passes.
The audit trap: LOE never shows schedule variance by construction — bury too much of a project in LOE and your SPI becomes decoratively meaningless.
Worked example
In a pipeline's EV structure: welding is discrete (earned per joint), weld inspection is apportioned (earned at 8% of welding's value), and the site office is LOE (earns its monthly budget by existing). When a review finds 30% of the budget classified as LOE, the controls lead reclassifies half of it to discrete — because a project that can't look behind schedule on paper eventually does so in reality, all at once.