Mean, standard deviation, extreme spread — and the part other tools skip: with five shots, an SD of 9 fps means the true SD is somewhere around 5 to 26 fps. This page shows you that range every time, because a ladder decision made on a five-shot SD is a decision made on a rumor.
Read this before you rely on any number here. Predictions use the standard G1/G7 drag models and the data you enter — they are estimates, not measurements, and they are never load advice. Confirm with live fire at distance. For anything you load yourself, work only from current published manuals (Hodgdon, Sierra, Hornady, Lyman), start low, and work up. TruingLog publishes no load recipes and suggests no charge weights.