It was clear late last year that the number of plug-in electric cars sold in the U.S. during 2017 would set a new record.
December is always a strong sales month for all vehicles, and dealerships across the country have rushed to deliver new cars, crossovers, and trucks to hit their year-end bonuses.
While the rise in sales of battery-electric and plug-in hybrid vehicles is clear, it hasn't necessarily been the booming year that some advocates hoped.
This year's sales appear to have exceeded last year's roughly 160,000 by perhaps 20 percent, surpassing 190,000 and perhaps even 195,000 but apparently just missing the 200,000 level.
Some of that has to do with production cadences: the new, longer-range 2018 Nissan Leaf will go on sale in January, and stocks of the old version have been all but depleted over the past few months.
Meanwhile, the Tesla Model 3 has been stuck in "production hell" for several months, in the evocative words of Tesla CEO Elon Musk. Only 1,810 were delivered between July and December last year.
2017 Tesla Model 3, 2017 Los Angeles Auto Show
Tesla managed to deliver more than 100,000 Model S and Model X cars worldwide for the full year, but its fourth-quarter Model 3 deliveries of 1,550 were at the low end of even the most pessimistic predictions.
It met its projection that for the first time ever, it would deliver more than 100,000 cars globally, against the 76,000 it delivered in 2016.
The company doesn't break down those sales by country, so we won't know exactly how many Model S and Model X electric cars it delivered in the U.S.
As for the handful of other high-volume plug-in cars, the Chevrolet Bolt EV ended the year with a bang. Its December deliveries of 3,227 gave it a 2017 total of 23,297.
While that's not the highest reported sales total for any month—in December 2016, its Volt stablemate hit 3,691—it's the highest total for any plug-in car in only its 13th month on sale.
Moreover, it suggests a plausible monthly sales average this year of 2,500 to 3,000 Bolts a month, or about 30,000 a year That's likely close to the Model S total, which of course we don't know.
2017 Toyota Prius Prime and 2017 Chevrolet Volt with Green Car Reports editor John Voelcker
Its Volt plug-in hybrid stablemate sold 1,937 last month, for a year-end total of 20,349. That's over the important 20,000 yearly total, though under the 2016 Volt total of 24,700.
The Toyota Prius Prime plug-in hybrid narrowly edged out the Volt for total 2017 sales, with 2,420 sold in December—by far its highest monthly total ever—and 20,936 for the full year.
As expected, the Leaf lagged in December: Just 102 were delivered, for a year-end total of 11,230. (Watch for the monthly number to starting rising this month as the first 2018 Leafs are delivered.)
The Volkswagen e-Golf delivered 343 units, its highest monthly number since May, for a 2017 year-end total of 3,534, slightly down on 2016's total of 3,937.
Among plug-in hybrids, the Audi A3 e-tron returned to its usual monthly sales level last month with 270 delivered after a dip into double digits for the three prior months. Its 2017 total sales were 2,877 (notably lower than the 4,280 in 2016, however).
Ford's 436 C-Maxi Energi hatchbacks were its lowest monthly sales since January 2016, reflecting last fall's discontinuation of the plug-in hybrid C-Max. The conventional hybrid version will end this summer as well.
The Ford Fusion Energi held steady at 875 for last month; full-year totals for both models were 8,140 and 9,632 respectively.
2018 Honda Clarity Plug-In Hybrid drive, Napa Valley, Caifornia, Dec 2017
Most impressive of all among plug-in hybrids, however, was the 898 Honda Clarity Plug-In models sold in December, only its second month on sale.
Honda also managed to deliver 527 Clarity Electric sedans, bring that battery-electric model's total to 1,105 sales last year over five months.
Year-end highs included the Smart ForTwo Electric Drive at 129 sold in December, for a 2017 total of 544 as the new version reaches more dealers.
Another was the Mercedes-Benz B250e hatchback at 111 for December, its highest monthly number in more than two years, giving it a full-year total of 744.
2018 Chevrolet Bolt EV
A handful of carmakers refuse to break out sales of some or all of their plug-in models, including BMW, Chrysler, Fiat, Hyundai, and Kia.
Thus far, none of those missing vehicles appear to have sales high enough in sales to move the needle.
Amusingly, 9 stray 2016 Chevrolet Spark EV electric minicars found buyers in November and December combined, raising that car's total 2017 sales to ... 23 units.
EDITOR'S NOTE: As of May 2017, this monthly report covers only plug-in electric cars with sales of 100 units a month or more—with occasional exceptions for new models, exceptionally large changes in sales volume, or other newsworthy events.