WASHINGTON (MarketWatch) — You may have heard recently that “truck driver” is the most common occupation in many states.

That’s a surprising fact unearthed by Quoctrung Bui, a diligent data analyst at NPR, and his story and chart were picked up uncritically by many other media outlets (including MarketWatch) and were featured on Facebook and Twitter feeds: “Why America is now a nation of truck drivers.”

It’s one of those examples where a statistic can be absolutely correct and utterly wrong at the same time. Although the story does reflect the data accurately, it doesn’t reflect the real world.

It paints a misleading portrait of America as a place where workers are still engaged primarily in manipulating physical goods, in moving material around from farms and mines to factories and then to stores. The America of big shoulders.

In reality, the American workplace is now largely one that sells things, or fixes meals, or shuffles information, or provides personal services to people.

We’re a services economy, not a “thing” economy.

About 2.8 million workers drive trucks around. That’s a big number, but it pales in comparison to other occupations. More than 21 million people work in office and administrative support, more than 14 million work in sales and more than 11 million work in food services. Nine million work in transportation or material-moving occupations. Heck, there are nearly 9 million production workers who actually make things.

Within those broad occupational groups, the government data break down occupations into ever finer detail, into 840 separate occupations. For instance, of 14 million who work in sales, about 8.5 million work in retail, and of those 8.5 million, about 4.5 million are classified as retail salespersons. (The rest are cashiers, or work at the counter, or sell parts.)

The most common occupations in America Retail salesperson 4.5 million Cashier 3.3 million Fast-food prep and service worker 3.0 million Office clerk 2.8 million Registered nurse 2.7 million Waiter 2.4 million Customer-service rep 2.4 million Manual laborer 2.3 million Secretary 2.2 million Janitor 2.1 million General manager 2.0 million Stock clerk 1.8 million Bookkeeper 1.6 million Heavy-truck driver 1.6 million Nursing assistant 1.4 million

The Bureau of Labor Statistics has a system, but it’s a bit arbitrary. The BLS classification system attempts to group together workers who have similar duties and skills, but it’s as much art as it is science.

For instance, the BLS sorts 7 million teachers into more than 80 separate occupations. (Special-ed teachers in elementary schools have a different occupation than special-ed teachers in preschools, middle schools or high schools, for instance.) But all 4 million retail salespersons are lumped into one large category, whether they sell lumber or lingerie.

That’s where NPR was led astray. NPR looked at a data set that aggregated various kinds of truck drivers into a single category but that didn’t aggregate other occupations in the same way. The sorting was inconsistent, so the comparison isn’t a legitimate one, and it makes us think that truck driving is the most common occupation in many states.

It’s not. Even if we put all 2.8 million truck drivers into a single category, there are still more office clerks, retail salespersons, cashiers and fast-food workers. There are nearly as many nurses, customer-service reps, cooks, waitresses, secretaries, janitors and material handlers.

If we look at data that is consistently disaggregated into the most detailed nonfarm occupations, retail salesperson is the most common job in 42 states. In four other states (Alabama, Louisiana, Maryland and Vermont), cashier is the biggest occupation. Fast-food worker is tops in two states: Kentucky and Ohio. There are more lawyers than any thing else in the District of Columbia, while office clerks are No. 1 in West Virginia.

But heavy-truck driver is the most common job in North Dakota.