South Saqqara Stone
The writing on the South Saqqara Stone means it is an important object. The list of pharaohs has details about the annual or biannual cattle count. This matches details in other lists such as the Turin King List. This allows archaeologists to work out how long each king ruled. From the information on the stone it can be worked out that  Teti ruled for at least 12 years, Userkare 2-4 years, Pepi I 49-50 years and 11-13 years for Merenre.