You would think that technology would have provided a way by now to get crowd counts and avoid the political fights over participation in the city's big annual rallies, like today's protest march.
But, unable to settle on a satisfactory method to tally the throngs passing through Hong Kong's streets, local police, academics and protest organisers continue to rely on a variety of relatively simple, low-tech methods. The results are likely to be at odds and subject to dispute.
'It would be a big day for Hong Kong if all parties can reach an agreement on how to count the number and if all these estimates are within reasonable range,' said University of Hong Kong social work professor Paul Yip Siu-fai, who does his own count each year.
In 2004, for instance, the newspaper Ming Pao took high-resolution aerial photographs to measure attendance at the July 1 rally. Grid patterns laid over the photographs broke the crowd area into smaller zones in which participants could be counted with better precision.
In the end, the newspaper estimated that 260,000 took part. That exceeded figures produced by three other methods, including the one used by police, but fell far short of the 530,000 claimed by march organiser the Civil Human Rights Front.
Robert Chung Ting-yiu, the director of HKU's public opinion programme, said Ming Pao's photographs were not clear enough, resulting in some marchers appearing lumped together.
It is also hard to pin down crowd sizes using such pictures because groups take up different amounts of space depending on the situation and environment, sometimes huddling together, sometimes spreading across the road.