There may be no better way to teach the principles of supply and demand than watching chicken wing prices. Those delectable scraps of poultry are the most expensive part of the whole bird.

Today, wing meat costs 58 cents more per pound than breast meat and $1.26 more than leg meat, according Agriculture Department data.

That’s because demand is high for chicken wings, all because of football. For years in the American poultry market there’s been a truism about wing prices: They peak at the end of January and beginning of February, coinciding with Super Bowl weekend.

But something is off this year. For the first time meat wholesalers can remember, wing prices are down as the Super Bowl nears. Nobody is entirely sure why.

Wings are about 20 cents cheaper per pound than they were this time a year ago and the year before that, according to the USDA.

There are two main theories as to why wing prices have flapped in the 2017-18 fiscal year.

The first has to do with yield. Chicken wings are about half bone and fat and half meat, so once you strip out all the inedible stuff, you’re actually paying four times as much for wing meat as you are for breast meat, said Erik Oosterwijk, president of Fells Point Wholesale Meats in Baltimore.

People could be getting tired of paying so much money for so little meat, he said, especially if the main draw to wings is Buffalo sauce. (You know, you can put Buffalo sauce on anything you want, not just wings.) You could just as easily take breast meat (Or Oosterwijk’s recommendation, thigh meat) and grill or fry it and serve with Buffalo sauce.

The second reason has to do with nutrition. In a serving of roast chicken, wings have 19.5 grams of fat, and breasts have 3.6 grams of fat, according to the National Chicken Council. Again, if the main operative of the chicken is to deliver Buffalo sauce, you can get the same sauce with a healthier cut of meat, Oosterwijk said.

Whatever the reason, the popularity of wings has been undercut as breasts and legs have become more popular. Chicken breasts are 21 cents more expensive now than this time a year ago, according to the USDA. Legs are 13 cents more expensive.

Don’t expect to see cheaper wholesale prices passed on to the grocery store or your local sports bar, though, Oosterwijk cautioned. Both businesses run on such tight margins, they can’t afford to slash wing prices every time the wholesale market fluctuates.

Oosterwijk sells a 40-pound case of wings — that’s about 250 actual pieces of meat — for between $100 and $120.

Even with the price declines, wings are still king of the coop. The National Chicken Council estimates Americans will eat 1.35 billion wings during Super Bowl weekend. That’s parts of 67.5 million chickens. Laid out end-to-end, a chicken could cross the road 13 million times.

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