The real workbook keeps three sheets: a Master System Tracker with per-system rollups (% installed, % in transform, % inspected, inspections outstanding), an Asset Register with a row per physical asset, and a System Deadlines lookup that the Master Tracker pulls forecasted due dates from via XLOOKUP.
This version keeps the same three sheets, but the Master Tracker's rollup columns are calculated live from the Asset Register and Deadlines data - no formulas to maintain or break. Sample data below is anonymised; upload your real workbook (same sheet names) to see it populate from actual data.
What this shows
Recognising a manual, formula-maintained rollup process and rebuilding it as a live, self-checking system - the same instinct as the inspection tooling, applied to the tracking workbook itself.
Originally three linked Excel sheets (XLOOKUP + COUNTIFS). Rebuilt here as a static web app - vanilla HTML/CSS/JS, SheetJS for reading uploaded workbooks. Nothing uploaded leaves your browser.