&gt; This is due to income, not job function<p>Its due to past circumstance, including past income, past life choices, inheritance, and a number of other factors. Its not a function of either present income or present job function, though its loosely correlated with both (and, of course, having <i>any</i> job function indicates that you are to some extent dependent on renting out your labor; really, the classes <i>aren&#x27;t</i> crisp categories, they are ranges on a continuum.)