Musannaf Ibn Abi Shayba 18:7

Abu Bakr narrated to us, he said: Abu Usama narrated to us, from Sa’id, from Qatada, that Umar ibn Abd al-Aziz set the blood money (diyah) at one hundred camels. And he valued every camel at one hundred [dirhams], whether they became expensive or cheap, and the people adopted it.