P.F. Chang cut its profit forecast and predicted a decline in same-store sales at both its Bistro and Pei Wei chains this year, and Panera Bread said its same-store sales are expected to come in at the low end of its previous forecast. Both chains say the economy and price increases are taking a bite out of business. "Many consumers have a strong affinity for our brand but (are) just finding them a bit too expensive for their everyday use," said P.F. Chang's Chairman and CEO Rick Federico.