Never gather it, until you know how it's going to be used.
Who is asking you to estimate, and what are they going to do with those numbers?
Until you explore and understand the answers to those kinds of questions, it's irresponsible to try to satisfy the request.
If you like the answers you get, then give the best data you can. If the answers you get suck, then you need to try to change how people are behaving. If you can't, then maybe you need a new job.
Comments
Remember the first rule of data:
Never gather it, until you know how it's going to be used.
Who is asking you to estimate, and what are they going to do with those numbers?
Until you explore and understand the answers to those kinds of questions, it's irresponsible to try to satisfy the request.
If you like the answers you get, then give the best data you can. If the answers you get suck, then you need to try to change how people are behaving. If you can't, then maybe you need a new job.