There can be hundreds of people especially on holidays and probably the summer. Depends on the weather as well. When I went, there was no line only to wait to take pictures, as that's when people start to take time taking pictures and such.
You hardly found a big crowd. During our visit, crowd was less except in the skydecks, where there was a queue of 4 or 5 persons.
Over 4,000 per day.
As such no idea but may b 800 or more
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