CHARLOTTE, N.C. (AP) ¿ Women's clothing retailer Cato Corp. said Thursday sales at its stores open at least a year rose 6 percent in September. The results prompted the company to raise its third-quarter earnings estimate. Sales at stores open at least a year are a key measure of retailer performance because they measure growth at existing stores rather than from newly opened ones. Net sales for the five weeks ended Oct. 4 climbed 8 percent to $70 million. Sales for the thirty-five weeks ended Oct. 3 rose 3 percent to $592.5 million, up from $577.1 million in the year-ago period. Given the higher-than-expected sales and margins, the company raised its third-quarter profit estimate to a range between 3 cents per share and 5 cents per share. The company previously forecast a loss of 3 cents per share to 7 cents per share. Analysts polled by Thomson Reuters forecast a loss of 3 cents per share, on average. Cato shares rose 84 cents, or 4.1 percent, to $21.34 in morning trading. The stock has ranged from $11.30 to $22.56 over the past year.