Rising costs and changing tastes have lead to less cereal consumption in the United States.

Consumption of ready-to-eat cereals began to decline in the early 1990s as prices of name-brand cereals rose along with the popularity of convenient breakfast foods such as bagels and toaster pastries. These trends continue.

Cold cereal, an option that's been around for 100 years, has been falling out of favor over the past two decades or so. Sales of ready-to-eat cereals fell 2.5%, to $6.4 billion, during a recent 12-month period, a time of rising grain costs, according to Symphony/IRI, which monitors sales at grocery stores and other retail outlets.

The longer-term trend represents a change in fortunes for the nation's leading cereal-makers, including Kellogg (K), General Mill (GIS) and Ralcorp Holdings (RAH).

So what old perennial favorites have felt the decrease the most?  Some popular brands lead the list - including Corn Flakes, Cheerios, Raisin Bran, Rice Krispies, Corn Pops, and Special K.