There were plenty of company announcements on the FTSE 250 on Thursday, providing some big swings in the market. The biggest mover was Ocado after the online grocer reported a festive surge with gross sales in the seven trading days before Christmas jump 23.8% from the same period in 2010. Shares were trading a massive 33% higher.Next in line, gaining a lesser (but still impressive) 11%, was building products distributor SIG after announcing profits before tax for 2011 will be above market expectations. House building group Barratt Developments climbed 9% after revenues rose 8% in the second half driven by a higher number of house completions and an increase in the average selling price.Investors were pleased with industrial services provider Cape's confident year-end trading update, with shares up 8%. The firm said that the strong revenue growth seen in the third quarter continued through to the end of the year, with higher levels of activity being seen across the majority of its geographies.IT services provider Computacenter rose after saying full year figures for 2011 will "show the sixth consecutive year of double digit earnings per share growth". Provident Financial, the door step lending company, has seen its shares jump 9% on news 'receivables' for 2011 - that is money it expects to get back from borrowers - will be marginally ahead of 2010.Car and bike parts retailer Halfords was in demand despite experiencing a tough third quarter. Group revenue fell by 2.1% in the last three months of 2011 however the firm did experience accelerated growth in the Autocentres division.As for the fallers, Home Retail led the decline after reporting weak Christmas sales for its Argos business. LFL sales at the catalogue shopping division fell 8.8% in the 18 weeks to the end of December.Shares in transport firm First Group fell on news the company now expects net cash generation to be in the range of £100m to £115m for 2011/12 due to fewer disposals as a result of the economic and regulatory climate. Booker, the cash and carry operator, fell despite seeing LFL sales rise 6.7% in the 16 weeks to December 30th.BCFTSE 250 - RisersOcado Group (OCDO) 73.85p +33.18%SIG (SHI) 101.80p +11.14%Barratt Developments (BDEV) 106.00p +9.28%Cape (CIU) 388.80p +7.70%Invensys (ISYS) 226.40p +5.06%Provident Financial (PFG) 996.50p +4.95%Moneysupermarket.com Group (MONY) 114.60p +4.85%Renishaw (RSW) 1,118.00p +4.78%Computacenter (CCC) 353.90p +4.40%Stagecoach Group (SGC) 282.30p +4.25%FTSE 250 - FallersHome Retail Group (HOME) 82.65p -5.27%Dairy Crest Group (DCG) 313.40p -4.68%Afren (AFR) 104.10p -3.88%Exillon Energy (EXI) 276.00p -3.16%Oxford Instruments (OXIG) 916.00p -2.55%Kenmare Resources (KMR) 49.06p -2.37%Booker Group (BOK) 73.15p -2.34%FirstGroup (FGP) 319.20p -2.24%Interserve (IRV) 306.30p -2.11%Howden Joinery Group (HWDN) 103.90p -2.07%