It is disconcerting to log in to find that your overall rating has fallen for no apparent reason. For example, my own has been as high as 96 on a couple of occassions, yet it is now 89.
I can understand that it takes a while to build up a 'readership' as one lodges Hub after Hub, but why should an overall rating fall when more and more people are actually coming in as 'readers' (hits) and 'followers.' Quite frankly, I cannot comprehend how 'Hubpages authority' as you call it, work it out.
As any moneys that one makes from this type of activity is negligible it really becomes simply a matter of vanity and, I guess if we're not happy we can simply cancel our registration, and transfer our material elsewhere. Lord knows there are enough sites who'd like to have us working with them.