To create a percentage attendance report for pupil premium (and non-PP) children, go to Reporting > Reports > Attendance (tab) > Custom Attendance Report.
Enter the date range required
In the far right column called 'Group Students By' select Pupil Premium then click Choose
*Tick to either include or exclude former students
The report will show two rows - Yes and No.
"Yes" is the data for the pupil premium students and one call "No" for the non pupil premium students.
If you want to see individual students data as well, you can run the report and 'Group Students By' both Pupil Premium AND Students by clicking one then holding down Ctrl on your keyboard to select the other -
The report will list students and include a column called 'PP' for Pupil Premium. If you type 'Yes' in the white filter box and hit enter this filters it for only your Pupil Premium eligible students -