There is a right way to condense 60 sheets into a story, and it starts with resisting the urge to open PowerPoint. The user's instinct to protect the original Excel file is correct, but the real challenge isn't technical; it's editorial. You don't aggregate first, and you don't build slides upfront. You define the single narrative that the stakeholders actually need, then let that narrative dictate every cut and every summary.
The practical sequence is deceptively simple. First, list the decisions or actions this presentation must enable. If the stakeholders walk away with one number, what is it? If they remember one trend, which one matters most? That becomes your spine. Then, map each sheet to that spine. Anything that feeds the story stays in a summarized form; anything that only adds texture gets dropped or relegated to an appendix. The original file remains untouched because you are not editing it; you are translating it. The 60 sheets are raw material, not a table of contents.
The skepticism about AI tools is fair, but it's also a symptom of a larger confusion. The problem is not whether a tool can read your confidential file; the problem is that no tool can decide what your stakeholders care about. That judgment is yours. A tool can help you visualize a pivot table or generate a chart, but it cannot tell you that the real story is a slowdown in Q3 fulfillment, not the overall revenue line. You are the only one who can make that call, and that is exactly why you should not outsource the thinking. If confidentiality blocks you from using cloud-based AI, that is a constraint, not a failure. It forces you to develop the skill that matters: the ability to reduce complexity without losing meaning.
So here is the concrete move. Take a blank page and write three sentences: what changed, why it matters, and what you want done about it. If you cannot write those three sentences after reviewing the sheets, you are not ready to open PowerPoint. Once you can, every slide you build should serve one of those three sentences. The 60 sheets become a reference library, not a burden. That is the difference between presenting data and telling a story. The tools will change; the discipline of deciding what counts will not.