No it hasn’t. There is no exact or predetermined added value for any business, after all.
It is extremely important to be able to measure the exact benefits of social media usage, as of all sales and marketing. Still, generalizing such results from one point to another would be as idiotic as claiming that every sales organization is exactly as productive and efficient. There is no absolute truth, not even though there’s more than plenty of different case studies.
There are all kinds of salesmen: poor, mediocre, and excellent. Likewise there are poor, mediocre, and excellent content producers. Some reach a mere 200 unique users a week with their uninteresting announcements, while others interact with hundreds of thousands weekly.
What constitutes the results of social media marketing then?
Direction*Quality*Quantity = Result
Direction: Are your resources directed to the right channels? To those, in which your target groups are today and tomorrow?
Quality: Is your content tailored for the interests of your audience and does it engage them?
Quantity: How many people in your target group are you reaching every day?
There are too many factors to estimate absolute figures for the added value of social media marketing. By measuring one’s own concrete results, one can quickly establish an understanding of the situation. Surely there are many suggestive studies that help in perceiving the range of possibilities.
Do you already know to whom especially you wish to talk to, how you improve your content, and how you grow your audience? Social media marketing is fun and, when planned well, also productive.