General reports - access older data

Hi Community,
When exploring a General report for a destination for a look-back window older than 90 days, will the Total Segment Population be smaller due to trait TTL, is the data not reliable back more than 90 days from present?

Example: Now, in May 2023, for last 30 days from January 1st 2023, looking to track total segment population for December 2022. 

Please share your thoughts or resources as I could't find anything that specific.