Methodology & Terminology
Calculation basis, report scope, and interpretation.
Standards and scope
Terminology is informed by PMI earned-value guidance and AACE Recommended Practice 10S-90. XER360 is not certified or endorsed by either organization. DCMA-style checks and XER360 diagnostics are screening tools, not a PMI/AACE compliance determination or contractual acceptance decision. Project specifications and the approved controls plan govern.
Calculation basis and limitations
Baseline and progress
PV is the sum of activity Baseline BAC x Schedule % Complete at the exact Current Data Date. BAC is the Baseline At Completion total (actual plus remaining resource and expense costs). Schedule progress uses the Baseline activity's current Start/Finish dates and calendar working time, bounded from 0 to 100%. Started activities use Actual Start; finish uses Actual Finish when complete, Remaining Finish when in progress, otherwise Planned Finish. Unstarted activities use Planned Start. This implements the At Completion values with current dates basis, not baseline actual history plus a remaining-cost spread. Missing required costs or activity dates make PV unavailable.
EV is an estimate
EV uses current resource budgets weighted by activity Physical % Complete. It does not implement all P6 WBS earned-value techniques. EV excludes expenses while PV, BAC and AC include them. Budget revisions and differences between current and baseline scope can affect EV/BAC and other EV-based indicators. Reconcile these inputs before contractual reporting.
Costs and forecasts
AC includes the selected project's resource and expense actual costs. ETC uses current remaining costs; EAC is AC + ETC. This-period AC is current cumulative AC less previous-update cumulative AC, including cost corrections.
Baseline cost distribution
The cost S-Curve reconstructs Baseline At Completion distribution directly from the XER; Excel is not required. Baseline actual regular plus overtime costs are spread between assignment Actual Start and Actual Finish, or Baseline DD. Remaining costs use assignment Remaining Start/Finish. Corresponding activity dates are used only when assignment dates are absent. Working time uses activity calendars or resource calendars for resource-dependent activities. This profile differs from activity BAC-weighted EVM PV; PV, SPI and SV retain their schedule-progress basis. Both values are identified at Current DD. Exact resource curves, manual spreads and stored Baseline financial-period timing are not reproduced. Missing calendars use disclosed elapsed-time estimates. Nonzero expenses or invalid required dates/costs withhold the Baseline distribution rather than silently omit costs.
Actual curves and units
Stored Financial Periods or P6 Distribution (estimated) changes only Current actual-cost timing, not Baseline distribution or EVM PV. With a valid Previous Update, estimated distribution retains its earlier actual-date spread and allocates the change in cumulative AC between Previous and Current Data Dates (end exclusive). This movement includes corrections and scope changes; multi-month intervals are split by elapsed schedule time, not claimed as recorded monthly expenditure. Without a valid Previous Update, Current actual-date distribution remains an estimate. Stored Financial Periods is never overwritten to force agreement with the update-movement card. Unallocated costs remain separate. Actual-cost percentage is budget spent, not Performance % Complete. Monetary values retain the XER's units; no exchange-rate conversion is performed.
Schedule review boundaries
- DCMA-style checks show screening criteria and applicable populations. The overall score is an XER360 summary, not an official DCMA or PMI score.
- The Critical Path Test performs a server sensitivity simulation, adding remaining working duration to a selected critical task and propagating relationships to completion. Unsupported conditions require verification in P6. No resource leveling is performed. Unavailable checks are not passing checks.
- Calendar comparisons use the two files selected in Compare. Dated exceptions show the affected date; workweek rules recur and do not have one edit date. Unmatched calendars may be added, removed, or renamed.
- Active out-of-sequence findings consider relationship type, lag, actual progress, and unresolved predecessor requirements. They are not a replacement for the P6 schedule log.
- Milestone differences are calendar days. Activity duration and total float use working-day conversion settings. They are not interchangeable.
Terms and formulas
- Planned Value (PV)
- Budgeted cost of work scheduled through the status date.
- Earned Value (EV)
- Budgeted value of work performed, measured using an established earned-value technique.
- Actual Cost (AC)
- Cost incurred for work performed.
- Budget at Completion (BAC)
- Budget for the defined scope, not the forecast cost.
- Estimate to Complete (ETC)
- Forecast cost of the remaining work.
- Estimate at Completion (EAC)
- Total forecast cost: AC + ETC.
- Cost Variance (CV)
- EV - AC. A positive value is favorable.
- Schedule Variance (SV)
- EV - PV, in cost units, not a delay measured in days.
- Cost Performance Index (CPI)
- EV / AC. Below 1 indicates unfavorable cost efficiency.
- Schedule Performance Index (SPI)
- EV / PV. Below 1 indicates less earned value than planned.
- Schedule % Complete
- PV / BAC x 100. Planned progress.
- Performance % Complete
- EV / BAC x 100. Actual spending is not physical progress.
- Total Float
- Time an activity can be delayed without delaying the applicable finish or violating a schedule constraint.
- Data Date
- Schedule status date separating recorded progress from remaining work.
- Baseline
- Reference schedule selected for comparison. Uploading a file does not establish contractual approval.
- CPLI
- (Remaining critical-path working time + completion Total Float) / remaining critical-path working time. XER360 uses exported P6 float and estimates remaining time on the completion calendar. Baseline/manual target headroom is shown separately as a completion target index, excluded from the DCMA score.
- Critical Path
- A driving path that determines project duration. Low float alone does not establish the driving path.