Basically, it has all been downhill for the once-dominant manual gearbox since the mid-20th century, with a rather dramatic dip in the new millennium.
"Manuals have gone from 20 percent of sales to 5 percent in the last 15 to 20 years," observed Mark Champine, who is in charge of drivetrain development at Chrysler.
The reasons for the manual's decline are to be found in the preferences of the American driver and the incremental, yet cumulatively, dramatic improvement in automatic transmissions. Today's automatics are much more efficient than they were even 10 years ago, and that efficiency has bred better fuel economy and performance, as well as smoother operation. The automatic's increased popularity has also meant lower initial cost through economies of scale.
A major impetus for the manual's decline, of course, is American driving tastes.
"Americans, with their cellphones and cups, don't want to be bothered with shifting," said Mark Gunderson, leader of a GM transmission engineering team. The cupholder, he suggested, is symbolic of the American motorist's propensity "to do things other than drive."
As it turns out, the preference for automatics triggers a vicious cycle. Chrysler's Champine noted: "As fewer people drive manuals, fewer are offered, and fewer are around to learn on."
Champine said he is now trying to find a car in which he can teach his 16-year-old daughter how to drive a manual.
"You do see less people growing up with manuals and learning to drive in them," said Dominick Infante, Subaru's communications director.
Another factor in the manual transmission's decline, GM's Gunderson said, is that it usually hurts resale value. So while an automatic tacks $1,000 or more on the sticker, it makes the car more valuable at trade-in time.
The increased efficiency of the modern automatics is most dramatically evident in the increased gas mileage they engender - a significant reason for their increasing popularity. Until relatively recently, automatics exacted a 1- or 2-m.p.g. penalty over a manual. Today, that difference has virtually vanished, with the automatic actually doing better in some applications.
An example is the 2014 Subaru Outback. That all-wheel-drive midsize crossover has EPAs of 22 city and 29 highway with the manual gearbox and 24 and 30 with the automatic.
No surprise, then, that 2014 was the last hurrah for the manual Outback, which was down to 1 percent of the model mix.
"It just didn't make sense to have the added manufacturing complexity and cost for that low a take rate," explained Subaru's Infante.
It does make sense, however, to offer a less-expensive manual transmission on Subaru's smaller, more price-sensitive cars, and on its BRZ and WRX performance models, which, Infante said, have a manual "take rate" of 90 percent.
As the manual take rate for those sporty Subarus might suggest, the automotive Rocky isn't down for the count.
"GM believes the manual transmission still has an important place in our portfolio," said Gunderson. "It's very important in our performance vehicles, like the Corvette and Camaro, and has a place in our small cars, like the Chevrolet Sonic and Cruze."