How to Read Billboard Impression Data

Every OOH conversation eventually gets to the same question: how many people will actually see my ad? The answer lives in the impression data, but those numbers can be misleading if you don't know what's behind them. An "impression" is not the same as a "view", and a 500,000 daily impression number can mean very different things depending on how the agency counts vehicles, dwell time, and angle of sight.

## What to Actually Look For

- **VAC (Visibility Adjusted Contacts)** — the gold standard, adjusts raw traffic for sight lines

- **Dwell time** — longer dwell (stops, slow zones) means higher effective impressions

- **Directional split** — does the counted traffic face your board or pass behind it?

- **Day-part breakdown** — impressions at 3am are worth less than impressions at 8am

At SkylineOut, every inventory card on our site shows the methodology behind the number. If you want a deep dive on a specific site, just ask and we'll walk you through the raw data.