(ShareCast News) - The FTSE 100 was down 0.28% to 6,130.15 in afternoon trading on Thursday, having gained X to Y, as oil slipped back and investors digested the slowest growth in construction since last April.Admiral led the risers, after it posted a forecast-beating and record 6% jump in full-year pre-tax profit as its car insurance customers grew. In the year to the end of December, pre-tax profit rose to £377m from £357m a year earlier, with customer numbers growing 9% to £4.43m. Its car insurance customers rose 14%, and profits from that business were up 11%.Investors were also upbeat about Rolls-Royce, which rose after it emerged that a further £640m of investment in the Trident upgrade was to be confirmed by Defence Secretary Michael Fallon in a written Commons statement. The announcement was expected to cover so-called long lead items for the first of the new boats, and funding for facilities at the Barrow shipyard and the propulsion system at Rolls-Royce's Derby facility.Slower sales at Whitbread in the fourth quarter saw shares in the operator of Premier Inns and Costa Coffee sink. Like-for-like sales at the firm's hotels and restaurants division increased 2.2% in the 11 weeks to 11 February, but Costa like-for-likes slowed to 0.5%. Total like-for-like sales were ahead 1.7%, well off the 3.5% achieved in the third and second quarters.Imperial Brands was also losing, after Goldman Sachs downgraded the tobacco company's stock to a neutral rating in a research note on Thursday. They currently had a 3,910p price objective on the stock, which would suggest a 3.59% potential upside from the company's previous close. The company had also launched a legal challenge to parts of Quebec's new tobacco control law in Canada this week, which would see more prominent on-pack health warnings, tighter advertising controls and a ban on flavoured tobacco and menthol cigarettes.Market MoversFTSE 100 (UKX) 6,134.90 -0.20%FTSE 250 (MCX) 16,755.90 0.16%techMARK (TASX) 3,143.51 -1.25%FTSE 100 - RisersAdmiral Group (ADM) 1,911.00p 8.58%Glencore (GLEN) 144.55p 6.76%Rolls-Royce Holdings (RR.) 715.50p 5.22%Intertek Group (ITRK) 3,001.00p 4.75%Standard Chartered (STAN) 475.50p 4.54%CRH (CRH) 1,933.00p 4.49%Centrica (CNA) 218.80p 3.94%Tesco (TSCO) 188.30p 3.66%SSE (SSE) 1,429.00p 2.73%Aberdeen Asset Management (ADN) 268.70p 2.67%FTSE 100 - FallersPersimmon (PSN) 2,000.00p -6.72%Whitbread (WTB) 3,828.00p -5.46%Inmarsat (ISAT) 913.50p -5.43%HSBC Holdings (HSBA) 453.40p -3.86%Carnival (CCL) 3,419.00p -3.20%ITV (ITV) 234.30p -2.74%International Consolidated Airlines Group SA (CDI) (IAG) 531.50p -2.57%Imperial Brands (IMB) 3,678.00p -2.56%Taylor Wimpey (TW.) 178.30p -2.19%Direct Line Insurance Group (DLG) 399.30p -2.08%