The following FTSE 100 companies will go ex-dividend on Thursday, after which investors will no longer qualify for the latest dividend payout. According to Reuters calculations at current market prices, the effect of the resulting adjustment to prices by market-makers would take 2.6 points off the index. COMPANY (RIC) DIVIDEND STOCK OPTION IMPACT (pence) Compass 12.3 0.75 Group Experian 31.25 (USc) 0.83 Land 11.72 0.32 Securities United 26.49 0.70 Utilities Group Among FTSE 250 companies going ex-dividend are: COMPANY (RIC) DIVIDEND (pence) Big Yellow Group 9.76 Edinburgh 9.2 Investment Trust Fidelity China 3.5 Special Situations Games Workshop 30 Mercantile 12.5 Investment Trust Newriver REIT 4.32 Syncona 2.3 Tate & Lyle 20.3 TR Property 7.55 Investment Trust Worldwide 22 Healthcare Trust (Reporting by Helen Reid, Editing by Julien Ponthus)