Pending means "unknown" and "not (yet) fixed".
To present this state in a Quaestor data set, Quaestor assigns the value -999999 to PENDING parameters.
Although this is a convenient way to distinguish "unknow" from "not available" or 0 (please realise this are three different cases/states for a parameter), realise that in the extremly small change of a value being -999999, it will be interpreted as pending.