In Segmentation Center, when you have an attribute from your First- or Third-Party Imported data in your audience definition, you will see two metrics - Reach and Addressable.
Reach is calculated as the number of devices for the attribute value(s) in your audience definition over the total number of devices matched in that first- or third-party data feed. It is not calculated against all data feeds coming into your Resonate account (as it was previously). Reach is not reflective of market reach or market penetration.
Here's an example to illustrate the Reach number: Let's say you onboarded 6 segments via a Third-Party data feed. Let's say in the entire data feed there are 10M matched devices. In the below screenshot, you have segment 1 in your audience definition, and the Reach number is 10%. This means that this segment represents roughly 10% of the devices in your data feed, or about 1M devices.
For Imported Data, the Addressable number reflects the number of onboarded records that match Resonate Profiles. In the example below, it’s 1.1 million IDs.
Learn more about managing your First-Party Data feeds.