Shares in Hershey rose over 4% today (28 January) after the US confectionery giant said it would up prices across a third of its portfolio.

The company, which last week booked a slump in annual profits, said it would increase wholesale prices on around a third of the products it sells in the US.

"The changes approximate a 3% price increase over Hershey's entire domestic product line and will help offset increases in areas of the company's input costs, including raw materials, fuel, utilities, and transportation," the company said.

Rising dairy costs have hammered Hershey's profits in the last year. The company's full-year income, which was also affected by restructuring costs, plunged 62% to $214.1m in 2007. Sales were flat at $4.9bn.

Shares in Hershey had risen 4.3% to US$35.51 at 12:40 EST.