PURPOSE: To obtain rank information among a plurality of objects to be measured through simple operation by calculating the section where the time difference between the objects to be measured is inverted based on measured results of split time and lap time.

CONSTITUTION: Time counting is started by pressing a start/stop switch 6 immediately after initialization. When lap switches 4 and 5 are pressed, the lap time of a first and second objects is written in the first and second LAP areas of the measuring area A of a RAM and, by counting the number of rounds of the first and second objects, the count values are written in the first and second number-of-round (n) areas of the area A in such a manner that, when the number of rounds is, for example, one, '1b is written. Then the lap time and numbers of rounds of the first and second objects are displayed 2. After the objects pass through some sections, reference processing is performed by pressing a reference switch 7 and the value of a change indicating the number of rounds at which the difference between the objects disappears when the objects run at the same paces is calculated. When the calculated value is smaller (larger) than '0', a reserve (not, reserve) message indicating a change (no change) in the order is displayed 2.