Established during the Western Han Dynasty, a person in this position was the superintendent for all county-level officials who had a stipend in excess of 600 dàn (石) of rice (roughly 775 bushels by today's standards). He was also in charge of inspecting the ancient equivalent of post offices (郵驛) for the county. However, these post offices would have only delivered official government documents. Each Commandery was divided into a number of smaller counties; each of these counties was assigned a postal inspector. This position was abolished in the Tang Dynasty.