

The McRib is back — even though pork prices are much higher than they were during previous seasons.
Why it matters: A popular theory holds that the McRib only appears when hog prices hit a low point:
"The McRib’s unique aspects and impermanence, many of us believe, make it seem a likely candidate for being a sort of arbitrage strategy. ... In this equation, the undervalued good in question is hog meat."
Willy Staley, The Awl, 2011
Between the lines: The McRib seems to have been consistently introduced at low points in the price of pork. Even this time around, the reintroduction comes only after pork prices have fallen significantly.