We use Simply Measured for most of our stats, and then put them in context within a written report so they're digestible. It's the system I was trained in, and the only one I really know, and way more efficient than compiling each platforms native insights, in my experience.

For bigger clients, we might make a complete deck. For those with smaller budgets and less urgency, we still have a graphic-driven one-pager that we build out in Mailchimp and export to PDF.

But mostly, we focus on highlights, suggest ways we can bottle and reproduce that success, and then provide a full engagement scorecard with a month-to-month comparison (what was better, what was worse, and a brief summary that explains why).

Finally, and sometimes it's just a flex depending on bandwidth, we do a competitive analysis, identify trends in creative development (e.g. new executions, emerging platforms).

And then I have one client that doesn't give a fuck about any of our assessments, and just wants the line-by-line excel sheet.

All this is to say that the best report is the one that helps your contact go back to their bosses and prove their success in scoping you.