Carrefour has sharply lowered its profit forecast for the current year. The French supermarket chain blamed the change on violent demonstrations at several locations across the country. Company officials said the unrest has weakened consumer confidence. Customers have been staying away from the stores, reducing traffic and sales at affected locations. The loss of store traffic is feeding directly into the company's expectations for sales and earnings this year. The resulting profit cut carried no specific figure, and the stores considered most affected were not identified.