The perfect attendance report tracks employees who have not had any absences in the past 30 days from the date you are viewing on the Insights tab.
*It does not take into consideration if they were late to a shift.
To view the Perfect Attendance report:
Go to the Insights tab
Scroll to the bottom to View All Reports/Tools
You should see this report closer to the top of that pop up
Unfortunately there is not a way to have a custom range for this report.
If you want to look at previous dates, you will want to:
Close out of the report
Go to the top of the Insights tab
Adjust the Date filter
Allow that load and go back down to the Perfect Attendance report
This will show the last 30 days from the date you selected, backwards.