Sales of plug-in electric cars in April held few real surprises, coming in at about the average rate of previous months.

The now-aging Nissan Leaf saw deliveries of 1,553 units last month, bringing the year's total to 5,638 and the total delivered in the U.S. since December 2010 to almost 78,000.

The Leaf is by far the world's best-selling electric car, with global sales expected to cross the 200,000 mark sometime this summer.

DON'T MISS: Plug-In Electric Car Sales Continue Rise In 2014, To 118,500

The range-extended electric Chevrolet Volt, meanwhile, saw 905 sales and leases in April, its highest monthly total since last December.

The Volt  continues its long, drawn-out wind-down before production of the new 2016 Volt starts later this year.

That brings the year's four-month Volt sales to 2,779, and overall sales since December 2010 to 76,136.

The Leaf passed the Volt last month to become the best-selling plug-in car in the U.S.

ALSO SEE: Tesla Motors Releases Quarterly Sales: 10,030 Cars Sold Globally Jan-Mar

"Truck and crossover sales have been strong all year," in the words of Kurt McNeil, U.S. vice president of sales operations for GM--a segment in which no plug-in vehicles are presently offered.

Spark EV is a shock

Perhaps the month's biggest surprise was the 920 Chevrolet Spark EV electric minicars sold and leased to both retail and fleet customers during April.

2014 Chevrolet Spark EV - Driven, July 2014 (NWAPA Drive Revolution)

2014 Chevrolet Spark EV - Driven, July 2014 (NWAPA Drive Revolution)

The little compliance car normally averages about 100 sales per month, though it sold 151 copies in March, its second-best total since the June 2013 launch.

But the April total of 920 is more than five times its previous-best total of 182 (in May 2014), and likely reflects the effects of price cuts in the three states where it's now sold.

As our colleagues at Autoblog Green pointed out in a tweet, that means the Spark EV actually outsold the Volt--for the first time ever.

RELATED: 2015 Chevrolet Spark EV Price Cut To $25,995; $139 Lease, No Money Down

Sales of the BMW i3, however, were down significantly. Last month's total was 406, the lowest number since last July.

The i3's four-month total is now 3,087, and 9,179 have been sold since sales began a year ago.

As always, Tesla Motors declines to report monthly sales broken down by country or region, so we don't know how many of its Model S luxury electric sedans it has delivered.

2015 Nissan Leaf

2015 Nissan Leaf

This report is customarily broken down with high-volume vehicles reported first: those that have sold more than 1,000 units a month over a number of months in the past.

They include the BMW i3, the Chevy Volt, the Nissan Leaf, and the Tesla Model S.

Plug-in hybrids

After that, we break out those vehicles--including plug-in hybrids from Ford and Toyota--whose sales range from several hundred to more than 1,000 in a few months.

MORE: Electric Cars: Some Are Real, Most Are Only 'Compliance Cars'--We Name Names

Sales of the Toyota Prius Plug-In Hybrid, which for many months was the third best-selling plug-in car in the U.S., continued at their new low pace: Deliveries haven't exceeded 1,000 units since last July.

Just 428 plug-in Priuses were sold last month, for a four-month total of 1,699--compared to 5,037 over the same period a year ago.

Ford delivered 553 C-Max and 711 Fusion plug-in hybrids, under its Energi sub-brand.

While higher than the low levels of January and February, the April numbers were still lower than March--and neither vehicle has crossed four-digit sales since last August.

The Honda Accord Plug-In Hybrid continues at minimal levels: as in March, just 5 were delivered in April. You might almost think it's a compliance car.

Low-volume and compliance cars

Finally, we end the roundup with the many low-volume and compliance cars, which customarily deliver monthly sales up to only 200 or so.

Among the battery-electric vehilces, sales of the Volkswagen e-Golf set a new monthly record last month, at 309--bringing the year's four-month total to 815, and the total since sales started last October to 1,172.

Sales of the Mercedes-Benz B-Class Electric Drive, however, held pretty much to its existing level, at 158 delivered in April for a year-to-date total of 652.

Total B-Class electric cars sold in the U.S. since the launch last July are now 1,426.

The little Smart Electric Drivesaw deliveries of 124 units last month, bringing its total deliveries over two years to within a hair of 4,000.

Smart won't break out retail versus fleet deliveries, however, and there's some suspicion that many of those are going to car-sharing services.

And Mitsubishi sold 16 i-MiEVs, bringing the four-month total to 31.

Then, moving on to range-extended electrics and plug-in hybrids, sales of the Porsche Cayenne S E-Hybrid were at 85 last month, outweighing the 30 E-Hybrid versions of the Panamera delivered in April.

Still, who might have expected Porsche to sell almost 1,500 plug-in hybrids (at prices north of $75,000) in just 17 months? (Not us, in any case.)

The Cadillac ELR range-extended electric sport coupe saw deliveries of 104 units in April. That brings total ELR sales for the four-month period to 415 and a total since it went on sale in December 2013 of just 1,731.

The ELR skipped the 2015 model year; the price of the upcoming 2016 ERL has been cut from $75,000 to $65,000.

The sexy BMW i8 gull-winged plug-in hybrid sport coupe logged 138 sales in April, bringing the year-to-date total to 479.

Finally, among the compliance cars, no Honda Fit EVs and only 4 Toyota RAV4 EVs were delivered--underscoring that those two vehicles really have ended their runs.

Ford delivered 124 Focus Electrics, and as noted above, a stunning 920 Chevrolet Spark EVs found homes--surely due to the generous incentives ending April 30th that Chevy instituted mid-month.

As always, Fiat Chrysler Automobiles refuses to break out sales of its electric 500e from total sales across many different models of the little 500.

Best guesses are that Fiat has now delivered between 6,500 and 9,000 electric 500s since December 2013--a higher number than expected.


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