The organic posts had the bigger reach, too, according to ComProp. The content was seen by 126 million users on Facebook and 20 million on Instagram, according to Facebook. New Knowledge says it suspects the latter number has been lowballed.

It’s surprising that a large part of the activity was on Instagram, part of the Facebook empire almost completely overlooked in the controversy. The Russian group’s Instagram accounts generated 183 million likes and 4 million comments, according to New Knowledge. On Facebook, some 31 million users shared the content and almost 39 million liked it, ComProp said.

The numbers suggest Facebook successfully restricted the scope of the initial debate to the paid ads on its main site as it attempted to limit the damage. The company’s first response to the exposure of the Russian group’s campaign was merely to make its political ad-sales practices more transparent. A crackdown on “inauthentic accounts” came later, and, as New Knowledge points out, some accounts linked to the agency still remain active.

It’s always been difficult to measure the impact of propaganda in print, radio or television. Given that Donald Trump outspent Clinton on Facebook, despite spending half as much as she did on the entire campaign, it’s tempting to think that digital ads are far more effective than traditional ones. Certainly, the audience and engagement numbers unearthed by the studies look impressive.

That’s not to say, however, that Russia’s campaign was highly efficient. According to ComProp, the methods the Russian campaign employed were lifted not from traditional political campaigns, but from digital marketing. And that provides the best metric by which to gauge their success.

In April, Brett Gordon and Florian Zettelmeyer of Northwestern University and two Facebook employees, Neha Bhargava and Dan Chapsky, published a paper on the efficiency of 15 Facebook advertising campaigns. Their most striking finding was that traditional observational methods – which look at how many people were exposed to an ad and how many bought a product – tend to overestimate grossly the true effect of ads.

The main reason? Many of the people exposed to an ad or an organic-looking post about a product would have bought it anyway. It’s no different with candidates or causes.