The records just keep on tumbling, as Toyota announces a new milestone for its Prius line of hybrids.

That figure is three million--the cumulative global sales total through June, for all Prius models since the car debuted in Japan in 1997.

Since then, the Prius has gone through three main generations, with other models--the Prius V wagon, Prius C subcompact and Prius Plug-In Hybrid--all adding to its impressive tally.

It's the second significant milestone passed in less than a year, Toyota announcing ain April that it had sold five million Toyota and Lexus hybrids in total, since that first 1997 Prius.

Such a figure puts the Prius' own success into perspective. While Toyota now produces a wide range of hybrid vehicles, it's the core line which still sells in the greatest numbers, and in certain locales--California being a prime example--it counts itself among the highest-selling cars of any type.

The car itself has changed significantly since that original car, first seen in the U.S. in 2000 as a 2001 model-year car.

Its 1.5-liter Hybrid Synergy Drive engine has expanded to 1.8 liters, while the car itself has grown from a large subcompact to something between a compact and midsize car--it's classed as midsize by the EPA thanks to its large interior volume.

Is the 2001-2003 Toyota Prius A Good Used Buy?

Despite this growth, the later car is significantly cleaner and more fuel efficient. Since 2007's EPA testing revisions, the Mk1 Prius is rated at 42 mpg city, 41 highway and 41 combined.

While those numbers are still better than many brand-new vehicles on sale today, the 2013 Prius is better still--51 mpg city, 48 highway and 50 combined. Such is the march of progress, as the latest Prius is also quicker, more refined and more comfortable than before. And while the looks don't suit everyone, many would agree it's easier on the eye, too.

The familiar Prius shape is likely to continue for some time to come, as recent spy shots show--though the current car's quirky interior looks like becoming more convetional when the 2015 car hits the market.

We wouldn't be surprised to see the fourth-gen car matching the 1,688,000 total sales of the 3rd-gen model, nor the 1,192,000 of the 2nd-gen Prius, either--hybrids are only getting more popular.

In fact, as far as hybrid sales are concerned, other carmakers have plenty of catching up to do...


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