CHICAGO (CBS) — Airfares are on the rise in Chicago and across the country, as fuel prices are hitting their highest level ever for this time of year.

As CBS 2’s Kris Habermehl reports, oil prices affect not only gasoline prices for terrestrial travelers, but also kerosene prices for airline passengers. Since commercial jet planes gobble up hundreds and even thousands of gallons of fuel, that extra cost is typically passed along to customers.

As of now, airlines are expected to charge between $4 and $20 extra for round-trip tickets. While that might not seem like that much of a difference from the consumer perspective, in aggregate for the airlines it will amount to millions of dollars nationwide.

Oil prices fell to near $90 per barrel Thursday, as Chinese inflation figures suggested authorities need to do more to slow growth and investors awaited a weekly report on U.S. crude inventories.

Still, that price is very high compared with the average for this time of year.

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