General strike, figures and electricity

There has been a huge expenditure of salive and ink on wether the Basque general strike of thursday was a huge success or a total failure. But here there is an interesting figure: Spanish electrical consumption fell by 4% on that day, what would imply that some 700,000 people did not work the 21st. There is absolutely no other reason for such absentism such as holidays or whatever, though, of course, it could be "a mere coincidence".
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