Automated Excel Comparison Macro

I need an Excel-based macro template that can sit inside a single workbook and, at the click of a button, compare two sheets (or two separately loaded files) then visually flag every difference it finds. My priority is to spot:

• Any row whose values no longer match the baseline, or where a value is now blank when it previously held data
• Completely new rows that appear in the updated file

All detected issues should be highlighted with colour coding that makes it obvious whether the problem is a mismatch, a missing value, or a brand-new row. Because the focus is on value changes rather than structural shifts, column order will be consistent; the macro just has to look cell-by-cell for discrepancies.

Deliverables
• A macro-enabled Excel template (.xlsm) with an intuitive “Compare” button
• Well-commented VBA so I can tweak logic or colour schemes later
• A short, embedded usage guide that explains where to paste or load the two data sets and how the results are reported

Acceptance criteria
The template must run in Office 2016 and later without additional add-ins, complete a comparison of 20,000 rows in under two minutes, leave the source data untouched, and clearly separate mismatch highlights from missing-value highlights and new-row highlights.

If this matches your skill set, let me know how soon you can turn the first draft around and whether there’s anything else you need from me to get started.