The first is invasion of privacy or confidentiality. Only information that is not generally knowable. Anyone can look and see that these people are not at work. Therefore, absence record is generally knowable and is not private information. Similarly, the reason for the absence generally is known.
Employees call in sick, plan vacations, and get called for jury duty.
Anyone who asks is told the reason for being gone. The information does not seem to be private. Another theory would be intentional infliction of emtional distress. Picking out the top 10 offenders doesn't seem an invasion of privacy, since anyone could figure it out from the posted sheets. Only if the conduct is so outrageous that it is beyond the bounds of a civilized society.