The Owner Month FTE (full-time equivalent) window is used to set the FTE value for an administrative unit. A "full-time equivalent" is a way of measuring the amount of labor available that puts all types of workers on an equivalent basis. For example, if your administrative unit contained three employees that worked a full, eight-hour day and two part-time employees that worked half-time, then this administrative unit would have an FTE value of 4.0.
This information is used in the Plan Matrix window when using the Level Labor by Existing FTE command.