How we source statistics.

Every number on this site cites its original source and the date it was published. You'll find them in the Sources list at the bottom of each page that uses them.

Numbers go stale. When a figure we cite is updated or contradicted by a newer source, we update it or remove it. If you spot a number that looks out of date, tell us at hello@bighint.com.

We don't invent benchmarks, and we don't round up. If a number comes from an observational study or a small sample, we say so next to the number.