Bizarrely, my EX FICO 8 dropped 2 points when an account that had reported at $6500 last month dropped to 0 this month.
My EX FICO 2 behaved less neurotically, adding 6 points.
The experian front end software said that this change in the account "could help or harm", while it said the other 4 utilization-reducing changes -- which included this change -- "could help".
I am very far removed from the 'all zero' penalty, having 20 other accounts with a balance.
So I am wondering why the 2 point loss?
Never mind. Mystery solved. On the same day that the balance dropped, another account increased, resting above several thresholds at a lofty 79% utilization.
Total revolving limits 741200 (620700 reporting) FICO 8: EQ 703 TU 704 EX 687