The forecast turns screens, hours and share of time into plays, and plays into impressions using each screen's measured audience. Here is the model, step by step.
Every JOLT screen runs a 64-second loop of eight 8-second spots. At 100% share of time that is 450 plays an hour. So a screen's play capacity over your flight is:
450 plays × hours in your daypart × days in the flight.
Multiply by the number of screens in your plan and you have the total plays available to buy.
A play is one showing; an impression is one likely viewing. Each screen has an impressions-per-play figure from audience measurement — how many people, on average, see a spot on that screen. Busy screens score well above one; quieter screens below.
Where a screen has its own measured playout history, the forecast uses it. Where it does not, the forecast uses the average for screens in that market. The report labels which basis your plan used: measured playout, network average or modeled estimate.
Impressions × CPM ÷ 1,000 = cost.
If that cost is more than your budget, the plan is budget-capped: you get budget ÷ CPM × 1,000 impressions, spread across the screens by your pacing. If it is less, you get everything the screens can deliver and the cost is the smaller figure. The forecast tells you which case you are in and how much of the available inventory your budget funds.
The estimate card also shows reach (people likely to see the campaign at least once) and frequency (how many times, on average). Both come from share of time: the more of a screen's plays you hold, the more often the same passers-by see you.
The forecast is an estimate. Your report shows what actually delivered, and you are billed on that. See How impressions are measured.