While May was a good month for sales of plug-in electric cars, the numbers sagged in June--and they appear to be doing the same for July.

Last month's sales data has now arrived, and it looks like the lack of new and exciting plug-in vehicles, plus buyers' continuing infatuation with SUVs, have kept plug-in sales roughly 30 percent below last year's levels for the same period.

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For July, 1,174 Nissan Leaf electric cars were sold, for a seven-month total this year of 10,990.

That was far lower than the 3,019 sold last July--the fourth-best Leaf sales month ever--and one-third lower than the 15,755 Leafs sold in the first seven months of 2014.

The July total, only one-third of last year's sales, may reflect the June 30 end of Georgia's generous income-tax credit for purchase of a zero-emission vehicle.

2015 Nissan Leaf

2015 Nissan Leaf

It may also mean Nissan is selling down its inventory of 2015 Leaf models before the announcement of the 2016 version, widely expected to carry a range rating that's perhaps 25 percent higher.

The Leaf still holds the title of best-selling plug-in electric car in the U.S., with 83,300 delivered since December 2010--against 80,300 Chevrolet Volts--but it clearly needs a shot in the arm to keep it competitive.

ALSO SEE: Will 2015 Plug-In Electric Car Sales Exceed Last Year's Total?

As for the Chevy Volt, it's effectively been on a two-year selldown before the all-new 2016 Volt lands in the first dealerships in September or October.

In July 2014, more than 2,000 Volts were delivered; this July, the total was 1,313. That makes a year-to-date total of 6,935 for 2015, versus 10,635 for the same period a year ago.

On the other hand, July represented the third month in a row of sales over 1,000 for the Volt, after four months of sales between 542 and 905.

2016 Chevrolet Volt

2016 Chevrolet Volt

That may indicated increasingly aggressive efforts by Chevy to clear the decks before the new model.

We'll be curious to see how quickly the new 2016 Volt launches out of the gate, and what effect its arrival has on Volt sales for the fourth quarter of the year.

The new Volt is improved in virtually every facet, with a more powerful engine, a higher range, and an occasional fifth "seating position"--all items highlighted as important by first-generation Volt owners.

MORE: Plug-In Electric Car Sales In June: Leaf, Volt Wane After May Surge

As for the BMW i3, one of the few plug-in cars that has sold more than 1,000 units in some months, July sales rose to 935.

That's the best monthly total since February, and an increase over the 363 from July 2014, when distribution was just getting established.

BMW has now delivered 5,391 i3s in 2015, as well as another 6,092 last year.

2015 BMW i3 REx - Driven, Portland OR, April 2015

2015 BMW i3 REx - Driven, Portland OR, April 2015

As always, we have no reliable monthly sales data for the Tesla Model S because the company refuses to release it.

As well as those high-volume entries, we'll report on sales of both plug-in hybrids and the more than a dozen low-volume plug-in entries available in at least some parts of the U.S. (meaning California and a handful of other locations).

The Volkswagen e-Golf had a good month in July, with 313 sales, its second-best of the 10 months it's now been on the U.S. market.

VW has delivered a total of 2,188 electric Golfs since sales began late last year.

Its German five-door hatchback counterpart, the Mercedes-Benz B-Class Electric Drive, racked up 196 sales, for a seven-month total of 1,368.

Altogether, Mercedes has now sold just about the same number of electric B-Class cars as VW has e-Golfs over a shorter time: In the 13 months since it first went on sale, the total delivered is now 2,142.

2012 Toyota Prius Plug-In Hybrid - production model

2012 Toyota Prius Plug-In Hybrid - production model

Plug-in hybrids

Sales of the Toyota Prius Plug-In Hybrid, now out of production, were 584 in July, for a seven-month total of 3,474. That compares to the 10,671 sold in the same months of 2014.

The plug-in Prius is now routinely selling below either of Ford's two plug-in hybrid models.

For July, the C-Max Energi five-door compact hatchback delivered another 693 units, pretty much on pace with its rate for the last year or more. The seven-month C-Max plug-in total is now 4,236.

As for the Fusion Energi mid-size sedan, July sales were 852, bringing its year-to-date total to 5,142.

Most likely reflecting the added interior space and cargo volume of the Fusion, its sales have largely exceeded those of the C-Max plug-in for the last 18 months.

2015 Ford Focus Electric, 2014 New York Auto Show

2015 Ford Focus Electric, 2014 New York Auto Show

Compliance cars

For the Chevrolet Spark EV, deliveries in July amounted to 57 units--the lowest number since last August, and the end to a string of three-digit months that started in February.

The Ford Focus Electric hatchback, now entering its fifth model year, saw sales of 135, for a seven-month total of 946, roughly staying at the same sales pace it's maintained for those five years.

Perhaps the electric Focus isn't a compliance car--as a few diehard Focus Electric owners maintain--but it's sure behaving like one.

No Honda Fit EVs or Toyota RAV4 EVs were sold in July, and neither car has logged a sale since April.

There are still a few RAV4 EVs in stock, but the Fit EV is now effective gone as a new car (limited numbers are available in a couple of states on two-year used-car leases).

2016 Cadillac ELR

2016 Cadillac ELR

Low-volume entries

The little Smart ForTwo Electric Drive minicar continued to sell at a steady pace, albeit one somewhat lower than last year.

Total deliveries for July were 109, bringing the 2015 total to 755 altogether--substantially down on the 1,390 sold during the same period last year.

The Cadillac ELR range-extended electric coupe logged 66 more deliveries, for a year-to-date total of 659. That compares to 188 last July, but a lower 2014 total of 578 for the same period.

BMW i8 sales for July were 217, an all-time high for the 12 months the plug-in hybrid sport coupe with the gullwing doors has been on sale.

The company has now delivered 1,505 i8s, an impressive total for a car with a base price above $130,000.

2015 Porsche Cayenne S E-Hybrid, 2014 Paris Auto Show

2015 Porsche Cayenne S E-Hybrid, 2014 Paris Auto Show

Porsche delivered 23 Panamera S E-Hybrids and 77 more Cayenne S E-Hybrids, bringing seven-month totals for its pair of plug-in hybrids to 253 and 563 respectively.

Beleaguered Mitsubishi delivered 12 i-MiEV battery-electric minicars in July, bringing its 2015 sales so far to a total of 84.

And, finally, one single Honda Accord Plug-In Hybrid was sold in July, bringing its year-to-date total to 60.

Like the Fit EV, that car has been withdrawn from the market; its total sales over three years add up to just 1,035 units.


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