I would consider a skyscraper any building which is at least as high as the Philadelphia city hall which was the highest skyscraper at the begining of the XX century.
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Hong Kong has the most skyscrapers. It has 294 completed buildings over 150 meters ( 492 feet ) I understand that this is not the cutoff point you set of 167 meters or 548 feet but their lead is so substantial over 2nd place New York city with 227 buildings above 150 meters. I am certain if we could break it down to the specific cutoff point you mentioned Hong Kong would still be the leader.