The 2013 Ford Focus. Photo credit: Ford Motor Company

All of the world's 2012 new-car sales numbers are finally in and tallied, and it's official: Ford's (NYSE:F) Focus was the world's best-selling car last year.

The compact Focus beat out the longtime champ, Toyota's (NYSE:TM) Corolla, thanks to strong sales around the world – particularly in China, where the new-generation Focus was launched to wide acclaim last spring.

Strong sales around the world
Every year, the respected auto industry analytics firm R. L. Polk compiles new-car registration data from every single country in the world. This takes a few months (which is why we're hearing about this in April), but the company's report is considered definitive.

Polk's report for 2012 says that the Focus was the world sales champ, with a whopping 1,020,410 units sold. Ford attributed much of the Focus's gains to big sales increases in both China and the U.S. (The Focus was also among Europe's best-selling cars, but Europe's economic woes hindered sales totals.)

Sales of the Focus here in the U.S. were up 40% in 2012, as the car was widely praised by reviewers for its solid feel and premium interior features. It has proven to be Ford's best-ever competitor for the class-leading Corolla and Honda (NYSE:HMC) Civic. In fact, the quality of the Focus seemed to catch the two Japanese giants off guard, driving Honda to rush a redo of its Civic to market months ahead of schedule.

Big growth in China, but there's a catch
But the big story for Focus last year was in China, and I should explain that there's a bit of controversy here. Ford actually sells two different cars called "Focus" in China: The current global model as sold here in the U.S., called "New Focus" and positioned as a premium product, and the last-generation European-model Focus, called "Classic Focus" and sold at more of an entry-level price.

The New Focus was launched in China last spring and was a hit with China's auto critics, for much the same reasons that the car has done so well elsewhere. And it has clearly done well with consumers. But it's hard to tell exactly how well it has done, because Ford rolls up the sales figures for the New Focus and the Classic Focus into one column labeled "Focus". (I asked Ford for a breakdown of last year's sales, but was told that the company doesn't provide them.)

So when I say that sales of the Focus were up 51% in China last year, it's likely true that much of that was due to the success of the new model, but I don't know for sure.

The upshot: 2012 was great for Ford
But either way, there's no question that the sharp-looking compact has been a huge success around the world for Ford.

And it's not the only success, as there were two other Ford's in Polk's top ten: The F-Series pickup, in third place, and the Fiesta, the Focus's smaller sibling, which was the world's best-selling compact car last year.

Clearly, Ford's renewed focus (so to speak) on building great small cars has worked out well for the company.

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.