Abstract: Apparatus for connection to the line finder group busy signal leads of telephone office equipment to determine when each line finder group is and is not busy, make an averaging determination of the busy conditions and generate signals indicating this average condition of busy activity on the monitored lines. The apparatus includes a parallel to serial multiplexer for cyclically sequentially sampling the line finder busy signal leads, means for selecting which of the leads are to be sampled, and a divide-by-N counter settable to count a predetermined number of pulses received from the multiplexer equal to the number of leads selected for monitoring, and to generate an output signal after each receipt of such predetermined number of pulses. The timing of the apparatus is so arranged that each generated output signal directly represents a busy time of 0.1% of an hour or 3.6 seconds.