Automakers that switched to reporting U.S. sales quarterly instead of monthly argued that the wider span gave a truer measure of their performance. There is some truth to that, as much as I have pushed for preserving the monthly standard.

But as most of the industry is taking the longer view, let’s go real long. As in 10 years.

We’re winding down a year ending in zero, so it’s as good a time as any to dive into the numbers.

Here are some trends I gleaned from a comparison of this year’s figures, most of them through September (sorry, that’s the latest we have for the entire industry), to those for 2010, courtesy of the Automotive News Data Center.

It’s been a fact of life through most of our lives that General Motors’ U.S. market share would plunge from decade to decade. It went from 50-something in the 1960s to 20-something before the Great Recession and bankruptcy.

The bleeding has largely stopped. In 2010, when GM was still selling some Saturns, Hummers and Pontiacs, its share was 19.1 percent. Through three quarters of this year, the company’s four remaining brands had a combined 17 percent share.

Footnote: In CEO Mary Barra’s tenure, which started in January 2014, when GM had 17.9 percent of the market, the decline has been less than a point.

A decade ago, it was a gradual climb from the No. 10 brand — Jeep at 2.5 percent — to No. 1 Ford, at 15.1 percent.

Today, the elite fall into three distinct groups.

The top three, then and now, are Ford (13.6 percent through September), Toyota (12.2 percent) and Chevrolet (11.6 percent), with Toyota and Chevy swapping places.

The middle third: Honda (8.5 percent), Nissan (5.7 percent) and Jeep (5.6 percent).

And the knotted final four: Hyundai, Ram and Subaru are all at 4.2 percent, followed by Kia, at 4.1.

The top three luxury brands remain Mercedes, Lexus and BMW. Lexus last finished first in 2010; its German rivals have swapped titles ever since.

Audi is a distant fourth. But it has leapfrogged Infiniti, Acura and Cadillac in the past decade.

Ford Motor Co. shed Volvo in 2010 (and Jaguar and Land Rover earlier) so it could focus on one luxury brand: Lincoln. This year — we have 11-month numbers for this comparison — Volvo has overtaken Lincoln, erasing a nearly 32,000-sale deficit over the course of the decade.

A 20-year perspective is helpful here. At the turn of the century, 83.7 percent of the cars and light trucks sold in the U.S. were made in North America. The figure had dropped to 76.4 percent by 2010. And it’s held steady since — 75.9 percent through September.

In 2010, six of the 10 bestselling vehicles were cars. Now, there are only two on that list: the Toyota Camry and Honda Civic. Meanwhile, the share of the market held by cars has nose-dived from 51.7 percent in 2010 to 24.5 percent through September.

There is some comfort for those who like to see traditions hold. The Camry has been the bestselling car in the U.S. for 18 straight years. And the Ford F-Series pickup has been the top-selling truck for 43.

A decade ago, Teslas barely existed. Today, to the fascination and frustration of rival executives, they’re a force to reckon with.

But how many is a different story. Tesla releases one sales figure. It’s quarterly and global — 318,980 this year through September. And now that more and more sales are coming from China and Europe, it’s impossible to decipher what’s being peddled in the U.S. Our Data Center pegs the nine-month tally in the Mercedes-Lexus range, around 200,000.

All of which prompts one final observation: CEO Elon Musk may be worth some $128 billion, but he’s worthless when it comes to helping the industry’s sales-number crunchers.