Although there are 18 products compatible with 4.0 (my selected filter), only 5 show when I choose to sort by monthly views. I’m guessing those with no views are omitted completely. Mine’s there, but thought I’d mention it anyway 
Yeah I think you’re right - it can’t sort if a page hasn’t had any views yet… I’ll see if I can default the views to zero in that case, thanks for letting me know!