Supermarket giant Albertsons is reeling from rising costs and cash-strapped shoppers flocking to rival discount stores.

Shares in Albertsons tanked more than 20% Thursday after the company lowered its financial outlook for the year and reported earnings below Wall Street expectations. The company's stock is down roughly 45% over the past 12 months.

Chief Executive Susan Morris said the Boise, Idaho, company is working to lower prices for certain items to win back market share, and is pushing back against suppliers' price increases.

"We fully expect to see cost increases as the fuel situation continues," Morris said. "We will work to not pass that through to the customer."