Collection Statistics

[Mondo Bizarro]

I apologize if this has been discussed already (I didn't see it), but how and how often are collection statistics updated? I ask because I just noticed the following:

Strongly overrepresented: Horror, Teen

Is this a known glitch or do the 1% of teen titles I have equate to some significance? Also, do new additions to your collection factor into your stats immediately? I just added a few titles but don't think some of the category numbers changed, although I can't be positive.

Thanks!