Ford's lineup continues to post sales gains in Europe. Image source: Ford Motor Company.

Understanding sales in the automotive industry is never as easy as it seems. Year-over-year comparisons can change thanks to quirks in the calendar and a varying amount of selling days. There's also a seasonal pattern that leads to a stronger spring and summer selling season, which could change because of the weather, such as a lengthy or particularly heavy winter. And then when you consider overseas markets, sometimes companies report a different set of countries within a region -- a good example is Europe.

So, with all of that said, let's take a look at Ford Motor Company's (NYSE:F) double-digit rise in European sales to try to understand if the result is as good as it looks.

By the numbers

Ford recorded healthy total vehicle sales and passenger car sales during May in its traditional 20 European markets (Euro 20). Sales in its Euro 20 markets rose 11.5% to just under 112,000 vehicles, which was good enough for its best May result since 2011.

Expanding slightly, Ford's European 22 markets' sales jumped double digits as well, by 10.1%, to 125,800 vehicles in May. In all of Ford's 50 European markets, Ford's sales increased by 9.9% to 128,500 vehicles last month. While those double digits look good, Ford's Euro 20 market share dropped 20 basis points to 7.6% and remains 10 basis points lower for the year-to-date figures.

Also, while Ford likes to use those markets in its press release because it focuses some of its sales efforts in different markets than some of its competitors, looking at the European Automobile Manufacturers Association gives investors a slightly different view of its sales.

EU and competitors' data

According to the ACEA, which looks at sales in the European Union specifically, Ford posted a 7.9% gain to 85,824 units. Last month's result was a slight improvement from Ford's year-to-date sales gain of 6.9% to 454,914 vehicles in the European Union. But because the region's sales have rebounded at a decent clip in 2016, Ford's market share moved 20 basis points lower to 7.1%, similar to Ford's own metrics for its Euro 20 markets.

For more context, a couple of Ford's closest competitors posted solid gains. Fiat Chrysler Automobiles (NYSE:FCAU), which heavily relies on its well-known FIAT brand in Europe, sold more than 96,000 units in the European Union last month, good for an impressive 25.7% gain compared to the prior year. While the Jeep and Lancia/Chrysler brands sold a much lower volume -- 9,501 and 7,488 units last month, respectively -- the brands both topped 31% gains compared to last year's May. The gains for FCA haven't been a one month wonder, either, as its FCA umbrella of brands has recorded an 18.1% surge in sales year to date.

Meanwhile, Ford's other Detroit competitor, General Motors' (NYSE:GM) Opel/Vauxhaull, posted a 12.6% gain last month to 86,588 units, just above Ford's level of sales in the European Union. GM's overall Opel group figure was slightly lower, an 11.9% gain, because the exit of its Chevrolet brand has dragged comparisons slightly lower for last month. However, the overall sales for GM's Opel group remain up double digits for the year at 10.2% to 432,939 units.

Ultimately, while sales figures and data from different markets make apples-to-apples comparisons between competitors difficult to slice through, the fact is, Ford's sales are doing well, and it's finally generating bottom-line profit in the region, even though it is losing a little bit of market share to competitors. However, as long as Ford is still churning out profit in the region, that's a huge step forward from the past few years, when it incurred billions in losses.

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.