PURPOSE: To simplify a selecting operation of oil feeding data to be adjusted, by a method wherein unadjusted data of a plurality of meters is all displayed by one and the same display means, and an adjustment is carried out by selecting data in a range concerned with a finger.

CONSTITUTION: A POS 20 inputs oil feeding data from a computer 1, stores them in a memory, and transfers them to a data input and output device 13 and an adjusting means 24. The data input and output device 13, based on the oil feeding data, issues a bill from a printer 17. The adjusting means 24 stores the oil feeding data as unadjusted data and displays a bill number and oil fee in one of empty ranges 26 of a display 25. A gas station worker receives money based on the bill issued by the data input and output device 13 and touches a range in a touch key in which the bill number is displayed. Then, if the received money is thrown into a money discriminating means 27, a total amount is displayed in another display 28. After that, if a setting button 30 is pushed, an amount determining means compares the oil fee and the thrown amount of money and carries out an adjustment.