Excel Gantt Progress Spreadsheet

I need a single, well-structured Excel workbook that lets me manage a works programme from start to finish. The core of the file should be an easy-to-use data-entry sheet where I can type each activity, its planned start and finish dates, and the current % complete. Strong data validation is important so dates stay in sequence and percentage figures stay within 0–100 %.

On the calculation side, the sheet must automatically work out duration, remaining days, and any variance between planned and actual progress. Wherever possible, keep the maths transparent—standard formulae rather than hidden macros—so I can tweak things later if needed.

A live Gantt-chart view is essential. As soon as I enter or amend an activity, the bar chart should update in place, using conditional formatting or stacked bar techniques to illustrate actual versus planned progress. A separate dashboard tab showing headline metrics—total tasks, tasks at risk, overall completion %, and perhaps a small burndown line—would round out the visual reporting.

Acceptance criteria
• Data entry sheet guards against invalid dates or blank mandatory fields
• Duration, variance, and progress percentages calculate automatically without running code
• Gantt view refreshes instantly when underlying data change
• Dashboard summarises key figures and prints cleanly on A4

Please build in a bit of flexibility so I can add columns or extra activities later without breaking the visuals. If you have sample files that prove similar work, that will speed up our start.