It’s notoriously difficult to measure the value of social media—but apparently not impossible. Social media specialist Vitrue looked at its clients’ data for Facebook to determine exactly how much a Facebook fan is worth, as AdWeek reports, and they came up with a number: $3.60.

Vitrue’s clients boast a combined 41 million Facebook fans. For the most part, each fan yielded an extra impression. They assumed twice-daily posts bringing in 60M impressions and used a $5 CPM, “meaning a brand’s 1 million fans generate about $300,000 in media value each month. Using Vitrue’s calculation, Starbucks’ 6.5 million fan base — acquired in part with several big ad buys — is worth $23.4 million in media annually.”

Not all brands are created equal. Vitrue found wildly divergent impression-to-fan ratios. Some marketers generated just .44 impressions per fan, while another saw 3.6 impressions. [Michael Strutton, chief product officer at Vitrue,] chalked that up to sexier brands having more engaged connections, giving them access to the news feed more often. The impressions are not unique.

The $3.60 figure is the value over the course of a year, but is only a basic figure, since it doesn’t take into account engagement value, or the value of secondary mentions (such as when your fan page activity shows up on a user’s profile, and someone who isn’t your fan sees the post).

What do you think? What are Facebook fans worth to your company?

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