I think your primary problem is that you don''t know.
Preliminarily...it is good news...and you might want to search what "0" means here. But...first of all...it may not mean what this conventionally means, and second of all...combined with first of all...the only reasonable way to know is to ask the source...the person who gave you the appraisal document.
Sorry to be hard on you. Likely...it means it''s ideally cut (as in AGS ideal for 0). Possibly, the cut is as good as nothing, thus zero..(but not really).
Again, ask your appraiser. That''s the best way. While you''re at it...ask them why it''s zero, and you''re good to go.