Government acquisitions rely on project scheduling for successful program execution. An integrated master schedule (IMS) allows all stakeholders to understand activity interdependencies and managers to make informed decisions about balancing program cost, schedule and scope. Of particular importance is how program costs are impacted due to scheduling delays.
The Government Accountability Office (GAO) recently released the GAO Schedule Assessment Guide: Best Practices for Project Schedules. The aforementioned document is a follow-up to scheduling practices presented in the previously published Cost Estimating and Assessment Guide. The new GAO scheduling document presents best practices which were developed with input from government, industry and academic subject matter experts in the areas of cost estimating, scheduling and earned value analysis. Following is a summary of GAO scheduling best practices:
Identify All Activities
An Integrated Master Schedule (IMS) should capture all activities that are required for successful close-out of deliverables and completion of the program. All undertakings should be captured regardless of whether or not they are the responsibility of the Government, contractor, sub-contractor, vendors or others. The IMS should serve as a collection point for all identified tasks, requirements, deliverables, decisions and reviews. A failure to include all required efforts will result in an inaccurate view of the resources required to complete the program.
When creating activity descriptions, naming conventions should be consistent with other related documentation such as contract line item number (CLIN), Statement of Work (SOW) paragraph, task codes or similar identifying systems. Maintaining this information in a custom schedule field as opposed to part of the activity name will allow for cross-reference with related documents and management tools.
Order All Tasks
It is important that the schedule incorporates logical relationships between tasks so that realistic start and end activity dates can be predicted. Every activity should have a predecessor task and a successor task, with the exception of the first and last milestones. The majority of tasks should be finish to start relationships and mandatory date constraints should be documented.
Ideally, lag and lead times should be avoided. Instead, decompose tasks into smaller activities when lag and lead times are present. When multiple predecessors are tied to an activity, the schedule should be reviewed to determine if predecessors can be linked to other tasks.
Resources are assigned to all activities other than summary activities and milestones and should be compared to total available resources. Both labor and non-labor requirements should be captured. Non-labor may include items such as subcontracts, equipment, machines, travel and facilities.
Resource requirements should be “leveled,” or adjusted to match availability of resources. If resource management occurs via several systems, such as a separate contractor-based resource management tool, then a defined process is necessary to provide schedule input for resource availability issues.
Budgets should be developed for labor and non-labor requirements so that all costs are identified. Resource requirements should be compared with the program budget and checked against contract cost constraints.
Determine Task Durations
Durations of activities are to be estimated assuming typical conditions. Estimates should not be unrealistically short to meet a desired completion date, nor should they include extra time in an attempt to mitigate risk.
Assumptions used to estimate durations must be documented. Assumptions may include opinions of subject matter experts, methodologies used and/or historical information.
Verify the Schedule is “Horizontally and Vertically” Accurate
Ensuring that the schedule is horizontally accurate refers to ensuring that products, work packages and outcomes are logically ordered and interdependencies have been identified. A horizontally accurate schedule supports realistic completion dates and identification of the critical path.
Vertical accuracy refers to a consistency between varying levels of schedule hierarchy; summary, intermediate and detailed. Dates, status and scope should all be consistent and integrated. Vertical accuracy allows program managers insight into how delays in lower level tasks will affect overall deliverables.
Validate the Critical Path
The critical path determines the program’s earliest completion date. Subsequently, any delays in critical path activities will delay the program finish date.
“The critical path is generally defined as the longest continuous sequence of activities in a schedule.”
It is important to review and confirm a software-generated critical path, as it is used extensively for program management. Critical path activities are the focus of risk mitigation for potential program delays. It is also important to review near-critical paths which have the potential to overtake the existing critical path.
Ensure Realistic Total Float
Total float is “the amount of time a predecessor activity can slip before the delay affects the program’s estimated finish date.” Being aware of flexibility in the schedule gives insight into the ability to accommodate delays and reassign resources if appropriate. In general, critical path tasks have the least amount of total float.
Perform a Risk Analysis
A risk analysis should be performed before a baseline schedule is established. The risk analysis should take into consideration best-case, worst-case and most likely task durations.
A risk analysis includes prioritizing risks by probability and impact. The analysis should include risk mitigation efforts necessary to meet a statistically acceptable certainty of completion by a specific date.
Update the Schedule
Managing and updating the schedule with actual start and finish dates allows for real-time insight into execution of tasks and mitigating risks. A reliable schedule is an essential tool for reporting status of the program and determining how variances will affect subsequent interdependencies.
Develop a Baseline Schedule
Setting a baseline schedule is necessary to measure progress against target completion dates. Configuration control should be used to manage versions of the baseline schedule.
The use of scheduling best practices for acquisition programs will allow for the most effective outcomes of program performance. Scheduling best practices should be used in combination with cost estimating to determine the cost impacts of schedule delays. A reliable schedule as well as an understanding of the cost impacts to schedule changes can help Government agencies manage acquisition programs more effectively.