My guess, and its a guess, but nothing at all. The reason for the change is probably due to government mandates forcing car companies to continually make their vehicles more fuel efficient year to year. Those EPA estimates are just that, estimates. So if the estimate was somewhere between 31 and 32 mpgs, Kia can say the Sportage does 31 hwy mpg in 2011 and 32 hwy mpg in 2012. Then they can point at those numbers and say, "Look, we're improving our mileage!"
I'm sure this will spark some debate, but that's my two cents.
2012 Kia Sportage LX, 2.4L AWD Signal Red
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