PURPOSE: To provide a method of processing data, which can enhance the reliability of the control of elevator traffic, using prediction values calculated from data including historic data by filter-processing the traffic data so as to prevent erroneous detection of an initiation or a completion of a large traffic volume time zone due to an instant change in the traffic volume.

CONSTITUTION: A second set time is compared with a duration of inputted traffic data when the latter becomes lower than a first value, and when traffic volume data exceeding a second set value is sustained exceeding a first set time, it is determined that a large traffic volume time zone is initiated, and when the traffic volume data exceeding the second set value is detected at first, a signal indicating the detection time zone is issued. If the traffic volume data lower than the first set value is sustained, exceeding the second set time, it is determined that the large traffic volume time zone is completed, and a signal indicating a time zone in which the traffic volume data becomes lower than the first set value is issued, thereby it is possible to record a substantial part of input data between the signals indicating both time zones.