Though not the OP, I'd say give it a week or 500 posts, whichever comes first. That would provide a good dataset. After a day we have 125 datapoints which should give us 500 in a few days. But I'll defer the decision to the OP. I'm just the OCP.

I have the data in an Excel spreadsheet and an Access database to crunch numbers. It looks like I can't post spreadsheet or database files, but I can post zips. I'll zip the files and post them at 250 and 500.