Go to the "Priced in" thread and read what 3BC says. The events are known in advance, the last values are known, the expected new figures are known, so its down to what the new figures actually turn out to be, whether they are better or worse than predicted. The strongest are the NFP (Non Farm Payroll) figures which come out on the first Friday of each month. Several websites/FX services give lists of the relevant events. But only Felix gives a good idea of how much movement the event may cause.