The Taipei City Police Department put the number of protestors at today's demonstration in Taipei City against the Cross-Strait Agreement on Trade in Services at 57,000 as of 7 p.m., the Executive Yuan quoted a source from the National Police Agency (NPA).
This figure includes more than 30,000 people from the Ketagalan Boulevard main stage to Jingfu Gate or East Gate (including the gate), over 200 from east of the gate on Xinyi Road, over 300 east of the gate on Renai Road, over 200 south of the gate along Zhongshan South Road to Roosevelt Road, over 15,500 north of the gate along Zhongshan South Road to Zhongxiao East Road, and over 10,800 surrounding the Legislative Yuan (excluding Zhongshan South Road).
The NPA said this estimate is based on a method developed by Professor Herbert Jacobs of the University of California, Berkeley, which divides the area occupied by a crowd into grids, then multiplies the grids by the average number of people packed into each grid. For today's sit-in demonstration, officials on the scene estimated an average of three people per square meter. This method is currently used in many countries such as the U.S., Korea, the Philippines, Thailand, Singapore and Malaysia.
The Zhongzheng First Precinct, which has overseen many large protests and public events in recent years, measures those road sections as follows (all figures in square meters):
Ketagalan Boulevard: 48x100=4,800
East Gate: 50x50x3.14=7,000 (excluding the gate itself)
Zhongshan South Road (East Gate to Qingdao East Road): 40x570=22,800
Renai Road (East Gate to Linsen South Road): 40x190=7,600
Xinyi Road (East Gate-National Concert Hall): 30x110=3,300
Zhongshan South Road (East Gate to Freedom Square): 40x190=7,600
Qingdao East Road (Zhongshan South Road to Zhenjiang Street): 200x15=3,000
The police said the crowd density used for its estimate was obtained by observers dispatched to these road sections. Using this method, the size of the crowd over the afternoon were approximated at over 26,300 at 1 p.m., over 81,000 at 2 p.m., over 87,000 at 3 p.m., over 116,000 at 4 p.m. (peak size), over 101,900 at 5 p.m., over 82,400 at 6 p.m., and over 57,000 as of 7 p.m. The Executive Yuan said it was pleased that the event concluded peacefully.