Publishing group Pearson yesterday said it was confident in its outlook despite weakness in its key US textbook market. The owner of the world’s largest education business, Penguin Books and the Financial Times said sales were up six per cent and operating profit up 13 per cent but declined to give a full set of figures. It said it has upgraded its earnings forecast from 80p a share to 83p. Chief executive Marjorie Scardino said: "We can't count on the trading environment to get any easier any time soon, but we do expect our durability and our innovation to continue to help us succeed." Pearson said its investments in education technology and developing markets had enabled its education business to grow seven per cent, with a one per cent rise in its US Education division, which accounts for nearly half of group sales. It is looking for acquisitions in fast-growing markets including Brazil and India.