All data about students in Pure, including joint supervision percentages, is imported from Banner, the College's student records system. Errors in student data need to be corrected at source - in this case in Banner - rather than directly in Pure. Pure receives updates from Banner on a daily basis.
If you find errors in Pure related to students you supervise, please contact your departmental administrator in the first instance to check that the Banner records are correct. If they are, please contact the Pure helpdesk at email@example.com for assistance, copying in your departmental administrator.