Where the sales amount reported by the business entity is found to be unusual, the collection authority-in-charge may, by referring to the circumstances of similar business and other information, determine the sales amount or tax payable and levy the delinquent tax. 营业人申报之销售额,显不正常者,主管稽征机关,得参照同业情形与有关资料,核定其销售额或应纳税额并补征之。