Spot basis bids for soyabeans were steady to firmer in the US Midwest on Monday afternoon, on stronger export sales, grain merchants said. Soyabean basis bids rose by 5 cents per bushel at Decatur, Illinois, a key location. Soya bids also rose at a river terminal along the Mississippi River and at an Iowa elevator. Shipping costs for vessels bound for the US Gulf ebbed. CIF soyabean basis bids were mostly steady to firm on strong exports and slow farmer sales.