# Discrepancy in trait versus segment device count

Learn how to compare segment size to the real-time segment size in Adobe Audience Manager.

## Description description

Environment

Issue
Example use case: The following data source is established to receive data: 000111 - Data Source to receive TestInternalCompany

Some segments using this data have been created. The 2 segments in question are:

1111111- Existing Customers without Home
222222- Existing Customers with Home

When looking at the segment size compared to the trait size there is a big difference.

Additionally, comparing the total segment size to the real-time segment size, there is also a big difference.

Example:

Existing Customers without Home
Unique Trait Realization size - (30 day lookback) 360,226
Total Segment population - (30 day lookback) 478,695
Real time Segment size - (30 day look back) 21,756

Existing Customers with Home
Unique Trait Realization size - (30 day lookback) 9,058,573
Total Segment population - (30 day lookback) 9,205,534
Real-time Segment size - (30 day look back) 199,191

The Solution below will explain this behavior.

## Resolution resolution

Solution
Here is how to understand the difference between:

1. Trait Unique Trait Realization (UTR) and Total segment population.
2. Real-Time segment population and Total segment population.

Trait Unique Trait Realization (UTR) and Total segment population

• If you want to compare trait’s data with segment, then it should be done on the basis of total population on both sides.
• UTR is just addition of new devices during that window, while total segment population is the total count of devices currently present in a given segment.
• Total trait population should align with total segment population, considering the Profile Merge Rules in your segment.
• If you are using Profile Merge Rule as “Last Auth + Profile Link Device Graph”, then higher total segment population is expected as Profile Link Device Graph, considers up to 100 devices per profile for segmentation.
• Comparing UTR with total with segment population is simply not a correct comparison.

Real-Time segment population and Total segment population

• Real-time segment population is the count of devices which are seen online in the give lookback window out of the total segment population.
• So if less devices are seen online, then the real-time count is expected to be less than the total segment population.