Modelling Procurement Deliveries for Earned Value Management Using Level-of-Effort Logic

Abstract

Procurement remains one of the least mature elements in most Earned Value Management (EVM) systems. Conventional CPM schedules typically represent material deliveries as single-point events or fixed-lag activities, which conceal delivery uncertainty and weaken compliance with DCMA schedule-quality criteria [1]. This paper introduces a Level-of-Effort (LOE) Delivery Modelling Pattern [2] that enables planners to represent procurement deliveries as a dynamic time span between the first dispatch and the final required receipt. The LOE provides schedule visibility through standard SS/FF logic, while earned value and cash-flow recognition occur only at discrete receipt milestones. This event-driven approach ensures compliance with AACE RP 79R-13 [3], 88R-15 [4], and EIA-748 [5], aligns BCWP, ACWP, and actual payment timing, and produces S-curves whose cost and liquidity profiles better reflect project reality. A practical EPC case study demonstrates improved schedule-logic quality, financial traceability, and audit readiness, establishing the LOE delivery pattern as a repeatable, standards-aligned solution for integrating procurement, EVM, and cash-flow control.