Staff at Apple's retail outlets like the new Grand Central Terminal store create about $278 in sales per hour for the company, and make as little as $9 an hour doing it.

The at New York's Grand Central Terminal is designed to showcase the computing giant's best-selling products amidst "very modest alterations to historic elements." Given the location and majestic surroundings, it's a safe bet the new Apple Store will pull in a bundle for the company.

Apple's with its 300-plus retail outlets is the envy of the industry. The company reportedly generates nearly $4,500 in annual retail sales per square foot of retail space where its products are sold, excluding online sales. That's in contrast to the annual sales per square foot plus online sales of companies like Tiffany ($3,070), Coach ($1,776), and Best Buy ($880).

Now Asymco's Horace Dediu has broken down what those boffo numbers and others from Apple mean in terms of how much revenue Apple pulls in per Apple Store employee.

It turns out that in 2010, Apple Store revenue was $481,000 per employee. It's at about $320,000 per employee through three quarters of 2011, according to Dediu. That projects to a dip from 2010's record numbers to $427,000 in revenue per employee for this year, though one would expect fourth quarter Apple Store sales to spike due to the holidays.

By comparison, JC Penney pulls in about $124,000 in revenue per year per employee. Apple's clearly doing something very, very right. And even more right on a company-wide levelApple reported sales of about $1.8 million per employee and profits of nearly $430,000 per employee for its fiscal 2011.

But what about compensation for said employees? Is Apple particularly generous when it comes to its retail employees, considering the gold mine of a cash cow they're a big part of making so profitable?

The answer to that is, well, not so much. Dediu reckons that the average Apple store employee creates sales at the rate of about $278 per hour. Wages for those employees, however, range from $9 to $15 per hour for salespeople and can reach $30 per hour for Genius Bar staff.

Oh, and Apple Stores don't do commissions.

Salespeople people outnumber Genius Bar staff at Apple Stores. But even assuming that half of staff is making the upper limit of $15 per hour as salespeople and the other half is making the upper limit of $30 per hour as Genius Bar docents, it would still mean Apple is pulling in about $11 and change per dollar it pays its Apple Store employees (and again, that's assuredly a low-ball figure).

Is the level at which Apple compensates its retail workforce in relation to how much revenue it generates an outlier in the world of big retail? Because it sure seems like it. Maybe Apple's non-compensation retail overhead is so high that all of these numbers are misleading. Or maybe Apple just knows that it can get lots of people to work at Apple Stores for $9 an hour.

Dediu refers to the giant gap between the cash Apple hauls in and what it pays its retail staff as Apple Store workers' "productivity." We'd guess there's probably another word for it, somewhere outside of the economist's lexicon.

For more, see PCMag's slideshow of Apple's new Grand Central Terminal store above.