Many Talent Acquisition departments are thinking through how they can use talent communities (or CRM, talent pipelines, etc - all more of less the same for the purposes of this post) to drive more job seekers into their hiring funnels.
I can't remember a conversation I've had with someone in HR where I brought up the idea of building out talent communities and they weren't interested. But, the majority of people are having a hard time putting a value calculation around using this sort of talent acquisition strategy.
Talent Pipeline ROI
I'm going to assume that you're following talent community best practices and so this post is really about getting to the value of what you're doing in terms of $$$.
I think about this value in two ways. One, talent communities can help you save recruiting fees. If you hire someone from your talent community and they are in the bucket where you'd typically spend a fee - then there is your ROI.
Secondly, we can think about the talent community members much in the same way a marketer would think about a "lead." Marketers are willing to spend money on adwords, etc to drive leads because they know a certain percent of them will convert to customers, and be worth a certain amount of money each. If 10 leads translate into 1 customer worth $100 to me, then each lead is worth $10.
In TA, there is a certain thought process to follow: we spend money on our top of funnel (sourcing, Indeed PPC, etc) to drive applicants because we know that a certain number of these applicants will convert into hires, and a hire is worth our cost/hire for a given position. You can use this methodology to get to a very specific ROI from your talent community.
That's the methodology we lay out in this video, along with some specific numbers: