 Ryholt relies instead on a statistical method and estimates the duration of Sheshi's reign to have been between 20 and 53 years.The method consists in tallying the seals of Yakbim Sekhaenre, Ya'ammu Nubwoserre, Qareh Khawoserre and 'Ammu Ahotepre with those of Sheshi.Then, knowing that the first four of these kings reigned for at least 30 years, implies that they have left between 7.5 and 20 seals per year while on throne.