Stacy’s Brain

Stacy's Brain is a searchable database of marketing and growth statistics, built as the collective memory of the trade. You can look up a number, read where it came from and see how much weight it can carry before it shapes a decision.

Every entry shows its source, its sample and a reliability tier from S to D, judged on methodology, sample size, age of the evidence and vendor interest. There are also research reviews, collections answering common marketing questions, paid media benchmarks and a weekly newsletter.