I took a full journey of route 973 from Stanley to Tsim Sha Tsui (Mody Road), and noted down the time when the bus arrives and departs, and the number of passengers getting on and off the bus at every stop. I have taken the departure at 17:45 on 2013-11-15, the bus used was 7003, which was an Enviro400 with total capacity of 90 passengers, including 47 seats on the upper deck, 23 seaks on the lower deck and 20 standees. I chose the departure at 17:45 mainly because I would expect it to arrive HKU at about 18:35, picking up the students finishing the classes at 18:20, and also the return commute at Sai Ying Pun. However, when I arrived Stanley bus terminus at 17:37, I saw the previous 973 just completed the loop and heading for Stanley Plaza, which impiled that the previous departure at 17:25 was delayed by about 10 minutes, affecting the amount of passengers getting on this bus.
Here are the data I have collected:
The result was a bit of disappointing since there were only 67 passengers crossing the harbour, not filling all the seats available.
The reason of not getting full might be attributed to 3 factors:
First, there was an enough supply of route 970(X) buses immediately before, which picked up all the passengers waiting for route 970. Starting from Queen Mary Hospital, this bus had to queue for a long time entering stops as there was a chain of route 970(X) buses getting passengers on board before this bus, clearing the long queue of passengers waiting at the stops. More specifically, the route 970 bus immediately before this didn't get full even at Water Street, the last stop before crossing the harbour. Therefore, the were only a few passengers left at the stops in Sai Ying Pun for this bus to pick up.
Second, the previous departure was delayed, leaving fewer passengers for this bus to pick up along Stanley to Aberdeen.
Third, it was already winter and the swimming season was already finished. The sunset was so early that darkness already came in when this bus was still at Deep Water Bay. At about the same time in September, all the seats would have already been filled after Deep Water Bay, with lots of passengers boarding at each of the beaches. However, this bus even skipped the stop at Deep Water Bay!
Despite these reasons, the usage of this bus was still three quarters, which could not be said as low, partly because a small bus was used, and partly because there was some genuine demand from Sai Ying Pun to Tsim Sha Tsui. It should be noted that more than half of the boarding passengers got on the bus in the area of $9.2, which indicated the main source of passengers of route 973 was in the northern part of the island instead of Stanley to Deep Water Bay. Another interesting point was that, the first alighting passenger got off at Aberdeen, and a few more passengers got off between Pok Fu Lam and Sai Ying Pun, accumulating to a total of 10 passengers alighted before the harbour crossing.
In order to get a high demand of route 973, I suggest observing the same departure at 17:45 on a weekday, however, in September when HKU has just started the term because September is still within swimming season and due to the effect of skipping lessons in university, the number of HKU students in campus is greatest at the beginning of the term and decreases gradually.