Persimmon raced into the top spot after the house-builder announced a cash return worth £1.9bn over the next nine and a half years, something that Peel Hunt has called a 'game-changer'. Meanwhile, underlying pre-tax profits increased 55% to £148.1m, higher than market expectations of £141.1m. Also rising was sub-prime lender Provident Financial, which reported a 12% increase in full year pre-tax profit, helped by lower bad debt charges. The firm, which posted a pre-tax profit of £162.1m compared to £144.5m 2010, said it was confident of further growth in the year ahead. Revenue for the year increased to £910.8m from £866.4m before. Heading in the opposite direction was AZ Electronic Materials after warning that it expects "the more challenging trading conditions that we experienced towards the end of 2011 to continue into the first half of 2012." UBM, the events and publishing group, also dropped lower, most likely as a result of the lower pre-tax profit which fell from £115.5m to £102m during 2011 after the group took a financing expense worth £20.9m. FTSE 250 - RisersPersimmon (PSN) 713.50p +13.80%Provident Financial (PFG) 1,140.00p +6.24%Taylor Wimpey (TW.) 52.70p +6.10%SDL (SDL) 694.50p +5.31%Bellway (BWY) 828.50p +4.81%Grainger (GRI) 111.90p +3.90%Barratt Developments (BDEV) 146.90p +3.89%Dixons Retail (DXNS) 15.00p +3.45%Laird (LRD) 174.60p +3.25%Imagination Technologies Group (IMG) 622.00p +2.89%FTSE 250 - FallersAZ Electronic Materials SA (DI) (AZEM) 288.90p -7.28%Allied Gold Mining (ALD) 113.20p -3.82%Euromoney Institutional Investor (ERM) 735.50p -3.35%Rank Group (RNK) 140.50p -3.17%Ocado Group (OCDO) 96.60p -3.11%UBM (UBM) 584.00p -2.91%Interserve (IRV) 295.30p -2.86%Perform Group (PER) 274.50p -2.66%Lamprell (LAM) 334.90p -2.65%Heritage Oil (HOIL) 183.60p -2.34%NR