The conventional demand target display device based on time information differing from the information used by electric power companies and electric power consumers causes a divergence regarding their demand values. Therefore, a demand target display device with a dual-purpose scale, which acquires AC signals based on the AC waveform of AC power from a power supply line, generates time information based on the acquired AC signals, transmits the generated time information via radio waves within a housing, receives the transmitted time information via radio waves within the housing, indicates the time on the dual-purpose scale based on the received information, acquires electrical energy consumption within a segment for a given target demand value including the current time, and indicates the relationship between the acquired electrical energy consumption within a segment recorded and a target demand value set for such segment, is proposed.