As spring arrives, sales of plug-in electric cars have traditionally risen from their winter levels.
During the months of May through August, monthly sales are usually among the highest of the year.
At least for May, that rule holds as strongly for 2015 as it did last year.
The Nissan Leaf, now the best-selling plug-in vehicle in the U.S. as well as the world at large, saw May deliveries of 2,104 cars.
That brings the year's five-month total to 7,742, and the total number delivered in the U.S. since December 2010 to more than 80,000 Leafs.
Last month's number may have been boosted by sales in the Greater Atlanta area to buyers rushing to beat the end of Georgia's $5,000 tax credit for purchase of a battery-electric car.
2015 Chevrolet Volt
The first-generation Chevy Volt, meanwhile, continues on its long wind-down. Assembly of 2015 Volts at the Detroit-Hamtramck plant has now ended, and the all-new 2016 model will start shortly.
Nonetheless, last month Volt sales surged: Chevy delivered 1,618 Volts, its best monthly figure since last August.
That brings the 2015 total to 4,397, and the total over four and a half years to 77,754.
As always, Tesla Motors refuses to report its monthly sales or break down its quarterly global delivery number by market.
U.S. sales of its Model S electric luxury sedan are likely somewhere between 800 and 1,500 units.
While sales of the BMW i3--both the battery-electric and range-extended versions--didn't quite return to levels of 1,000 a month or more, the May deliveries of 818 were much better than April's anemic 406.
The five-month total for the i3 is 3,906, and BMW missed the magic total of 10,000 since going on sale last May by just three units.
2015 BMW i3 REx - Driven, Portland OR, April 2015
Another German small electric hatchback, the Volkswagen e-Golf, racked up record sales: It sold 410 units, its best month since going on sale last October.
That brings its five-month total to 1,225 delivered (along with 357 more at the end of last year).
The Mercedes-Benz B-Class Electric Drive--roughly the same size, but pricier than the e-Golf and i3--saw 278 deliveries, its second-best month since going on sale last July.
A total of 930 electric B-Class hatchbacks have been sold over the first five months of 2015.
Moving across the German border to the Alsace region of France, the Smart Electric Drive delivered 102 units, one of the few cars lower than last month. The two-seat minicar has sold or leased 930 altogether this year.
Plug-in hybrids, low-volume models
California's green stickers giving plug-in hybrids access to the carpool lane with only a sole occupant are now all but gone.
2012 Toyota Prius Plug-In Hybrid, Catskill Mountains, NY, Oct 2012
Between that and production of the current-generation Toyota Prius Plug-In Hybrid ending this month, sales of that vehicle will likely fall to minimal levels within a few months.
Still, Toyota managed to deliver 727 plug-in Priuses last month--the best monthly total since last August. That brings year-to-date sales to 2,426 and the total number of Prius Plug-Ins delivered in the U.S. to more than 40,000.
Sales of Ford's two Energi models, plug-in hybrid adaptations of the Fusion mid-size sedan and C-Max compact tall wagon, were 986 and 715 respectively.
While both numbers were up substantially from last month's sales, Ford's five-month totals for 2015 are both lower than the same period last year: 3,563 plug-in Fusions this year against 4,296 last year, and 2,876 C-Max plug-ins in 2015 against 2,940 in 2014.
2014 Chevrolet Spark EV - Driven, July 2014 (NWAPA Drive Revolution)
The 14 different low-volume models offered in parts of the country range from compliance cars like the Chevrolet Spark EV to pricey luxury models like Porsche's two plug-in hybrids.
The Cadillac ELR delivered 116 units, bringing its five-month total to 531 sales. That's consistent with its sales level over the past year and a half.
The BMW i8 plug-in hybrid sport coupe beat the ELR by one unit last month, at 117, bringing its 2015 total to 596.
The pair of plug-in Porsches sold 21 (for the Panamera large luxury sedan) and 105 (for the Cayenne SUV), bringing their 2015 totals thus far to 196 and 398 respectively.
2014 Porsche Panamera S E-Hybrid, Catskill Mountains, NY, Apr 2015
Sales of the Chevrolet Spark EV, meanwhile, fell from April's extraordinary 920 units to 283 units, still its second-best month since it went on sale in June 2013.
Annalisa Bluhm, of Chevrolet communications, notes that the carmaker has requested additional units of the Spark EV from its assembly plant in South Korea.
No Toyota RAV4 EVs or Honda Fit EVs were delivered, as those two compliance cars have now completed their missions.
In fact, Honda noted sales of the Fit EV were "-1" for May--the first time we've ever seen a negative number listed for sales!
Sales for the Ford Focus Electric were 165, the best number since last November. But this year's five-month total of 659 electric Focuses was lower than the 2014 figure for the same period of 699.
The tiny Mitsubishi i-MiEV delivered another 18 units last month, and there were also a mere 5 Honda Accord Plug-In Hybrids sold.
And as always, the makers of the Fiat 500e and Kia Soul EV refuse to release sales figures for their battery-electric vehicles.