It's a surprise to see my dead startup TutorialTab as #6 in weekly growth! Seems like your algorithm is sensitive to fluctuations in sites with really low Alexa rank (TT is at 13,890,005 right now). FYI!
Update: It went from 21,369,458 to 13,900,665 in the past week - so I probably need some sort of lower bound for these. In some cases that can indicate an up-and-comer, and I am even using a log scale for the delta so this a pretty serious outlier. Thanks for letting me know it is dead though, i will remove from the DB.
Many of the companies on that list have ranks somewhere in millions, which can fluctuate quite easily, and many of the companies have been around for months or years.
Edit: Accelgolf seems to be dead too. Blog & website broken and no updates for two years on twitter, linkedin indicates the founders have moved on.