An additional interesting number is the number of hours that freelancers have worked on this project, if that wouldn't be telling too many secrets.
(I have always paid by task, not by hour -- as you might have noticed I tend to center on small, well-defined projects with easily verified deliverables. I cultivate trust with my freelancers such that they know I'm not going to screw them on a neverending scope-creep deathmarch for the $400 project. Thus, I've really got no clue whether they're taking their sweet time doing projects or figuring out ludicrously efficient ways to do them and earning more per hour than I do -- and if they have done that, bully for them.)