Reply #5: Here's how they said it was done..... [View All]

[Lars39]

http://biz.yahoo.com/prnews/040425/nysu015_1.html

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Using standard crowd estimate methods, March participants were counted in designated grids on the National Mall, which are designed to hold a predetermined number of people. The March also verified this count by assigning 2,500 volunteers to stand at key entry points to the March area and at bus drop-off locations and count people by placing March stickers on participants as they entered these entry points.