"People are suspicious. They say, 'Well, if you are going to exclude two key prices -- energy and food -– well, yes you can keep the inflation rate low, and isn't that a problem?'" says Dr. Walden, a professor of agricultural and resource economics. "Well, the reason ... that economists like to look at this core rate of inflation is because traditionally we have seen energy and food prices bounce around. One month they'll be up, another month they will be down and so you get this up-and-down movement in the inflation rate, and it doesn't sort of give you a good view of the trend. So that's why the core rate is used.

"But this assumes ... that we will have these counterbalancing price changes in things like energy and food, and actually if you look over the last five years as I think most people would simply know from their gut, energy prices have been trending upward," he adds. "They've gone down a few months, but they have gone up more than they've gone down. So I think this is causing some economists to rethink how much focus to put on the core rate of inflation.

"I think the bottomline here is ... you want to look at this core rate," Walden concludes, "but you also want to look at the overall inflation rate that does include food and energy."