
Why does the stock price during earnings change so fast?
When companies report earnings, usually the price of the stock changes almost immediately. For example, two days ago Netflix released their earnings and the stock plummeted less than 20 seconds after the earnings call began. I don't understand how that is possible, how do traders know how to trade what to do before the financial facts are even reported during the call? Are there documents that are made public immediately when the earnings call begins? Or is this a case of speculation being right?