Currently all history hypertables have the same retention policy setting in the Housekeeper settings.
Let's say you want to keep less textual data as it takes up more space than numerical data, but you want to keep the same amount of numerical history data. Currently If you lower the history retention period, it will apply the settings for all the history hypertables.

This feature request suggests to split the history tables retention policy into 2 parts, one configurable retention policy would be for numerical data (history, and one for textual data.