Pingyu 平餘 "surplus on the scales" or yuping 餘平 was a surcharge levied in addition to the standard tax. The surcharge was in the early Qing period 清 (1644-1911) directly delivered to the Ministry of Revenue (hubu 戶部) and served to supplement the salaries of the Ministry's staff. The height of the pingyu surcharge was 2.5 per cent, and in this shape it was called suiping lougui 隨平陋規.
The Yongzheng Emperor 雍正帝 (r. 1722-1735) allowed that a large deficit in the Ministry's budget was covered from the pingyu surcharge. Thereafter the Ministry and the local administration decided to share the revenue from the pingyu and to use it mainly for the so-called anti-corruption allowance (yanglian yin 養廉銀). In the individual districts, the surcharge was either levied in shape of the transport-loss surcharge (huohao 火耗, see haoxian 耗羨), or in addition to the latter.
In Sichuan, for instance, for each 100 tael/liang of tax, 0.6 liang were levied in shape of the pingyu surcharge. This often happened clandestinely by manipulating official scales by which the tax was weighed, not seldom by ten per cent or more. The lougui, commonly translated as "customary fee" was therefore perceived as an "unsavoury fee". The Qianlong Emperor 乾隆帝 (r. 1735-1796) strictly forbade this bad habit, and issued standard weights and steelyards (dengtou 戥頭) to be used by the authorities. Yet in this way, the illegal pingyu surcharge became a legal fee and was regularly used to cover the running cost of the local district yamen.