The custom data displayed in metric viewer is different from input that user fills in.
For example in fig below have selected start date 1st Aug to 20th Aug. Today is 21st Aug. The data will show between 2nd Aug to 20th Aug.
In fig below the start date from 1st July to 10th Aug but the data show 12th July to 10th Aug.
Release : 20.3.3
Component : UIM OPERATOR CONSOLE - METRIC VIEWER