US bakery chain Panera Bread has said that February system-wide sales at stores open at least 18 months fell 1.9%, due in part to freezing weather conditions in some parts of the country. The Missouri-based company stood by its first-quarter and full-year profit forecasts. It has forecast earnings of 24 cents a share in the first quarter and 99 cents a share for the full year, matching analysts' forecasts.