Chicago was the most expensive market in the nation for whole milk in 2005, averaging $3.96 a gallon. In the first half of 2006, it has slipped to second behind New Orleans, which has Hurricane Katrina to blame.

For 2 percent milk, Chicago does a little better. It was the fifth-most expensive market in the nation in 2005--at $3.58 a gallon--in the USDA's survey of 30 urban markets. So far in 2006, Chicago has slipped to seventh place for 2 percent milk.

In comparison, a gallon of milk in Carbondale, Ill., just five hours away, was among the cheapest in the nation last year, averaging $2.68 for whole milk and $2.55 for 2 percent.