Allergies are the result of a hypersensitive immune system. The allergic immune system misidentifies an otherwise innocuous substance as harmful, and then attacks the substance with a ferocity far greater than required.
Laying off an employee is different from firing an employee. Firing means letting a worker go for any reason, whereas a layoff refers to an employment termination based on economics, usually involving more than one worker.
Lawyers: The number of billable hours in a month. Factory Worker: Number of parts assembled in a day. Clerical Worker: The number of key strokes made in a day. However, for many job titles, it is not clear how productivity should be measured in terms of production counts.