UK stocks were slightly lower by Tuesday lunchtime with markets pausing for a breather after hitting multi-year highs, as investors awaited economic data and corporate earnings in the US.So far in January, the FTSE 100 has risen nearly 400 points, representing a 6.6% jump. Stocks initially started today's session on a positive note after the forward-looking German GfK consumer confidence survey increased from 5.7 to 5.8 in February, ahead of forecasts for no change. However, with no other major economic indicators due for release in Europe today, the focus now turns to US consumer confidence figures and a barrage of corporate earnings Stateside later on. Bellwethers including Ford, Amazon and Pfizer are scheduled to report quarterly earnings today. Stock futures on Wall Street are pointing to a slightly lower start after the opening bell in the coming hours.Meanwhile, as the Federal Open Market Committee (FOMC) gathers today for its monthly meeting, analysts widely expect the third round of quantitative easing (also known as 'QE3') to continue well into next year. According to a Bloomberg survey, the Fed could buy $1.14tn of assets before the programme ends in the first quarter of 2014.Tomorrow will see the conclusion of the FOMC meeting, along with the release of fourth-quarter US gross domestic product (GDP) figures, which are sure to keep investors nervous for the time being.FTSE 100: Anglo up despite massive impairmentDiversified mining group Anglo American gained despite saying it will recognise a $4.0bn impairment charge in its 2012 results after completing a detailed cost and schedule review of its Minas-Rio iron ore project in Brazil.Banking group RBS was a heavy faller this morning after Espirito Santo downgraded its rating on the stock to 'sell'. Goldman Sachs downgraded RBS to 'sell' yesterday, saying that the lender is the "most exposed to near-term regulatory risk".Real estate giant British Land was subdued this morning after a third-quarter trading update. The group said it continued to perform well in the third quarter and saw "encouraging" levels of demand in spite of tough market conditions. Consumer products giant PZ Cussons fell despite posting a rise in profits in line with market expectations. The company, which owns Original Source shampoo, Morning Fresh washing up liquid and Imperial Leather soap, reported a 9.7% increase in profits before tax of £44.1m for the six months to November. Panmure Gordon said that results were in line with forecasts.National Grid was flat early on. The company reported "solid performance" reflecting good financial delivery for the October-January period.FTSE 250: Strong final quarter for William HillBookmaker William Hill was a high riser after saying its good performance continued into its final quarter after strong trading in retail and online. Net revenue grew by 12% in the 53 weeks to January 1st while operating profit was up 20%.Carpet and floor coverings retailer Carpetright was lower even though it said store refurbishments and an expansion to its laminate floor and bed ranges helped drive domestic sales in the third quarter.Under-pressure coal miner Bumi plc fell as its boardroom battles escalate. The group this morning recommended shareholders vote against resolutions put forward by founder Nathaniel Rothschild to get rid of most of the company's directors, saying that the proposed changes are "not the way forward".Diamond producer Petra fell despite reporting a 54% rise in first-half revenue. The company said that production had increased by 31% to 1.2m carats in the first six months of the year.FTSE 100 - RisersAnglo American (AAL) 1,918.50p +2.46%Evraz (EVR) 298.10p +1.50%Johnson Matthey (JMAT) 2,415.00p +1.39%Old Mutual (OML) 190.50p +1.11%Eurasian Natural Resources Corp. (ENRC) 335.00p +0.90%Rio Tinto (RIO) 3,537.00p +0.88%Imperial Tobacco Group (IMT) 2,444.00p +0.87%BP (BP.) 472.45p +0.85%Vodafone Group (VOD) 172.45p +0.79%Petrofac Ltd. (PFC) 1,722.00p +0.76%FTSE 100 - FallersRoyal Bank of Scotland Group (RBS) 349.20p -5.06%BT Group (BT.A) 244.60p -2.98%Aggreko (AGK) 1,700.00p -2.69%Barclays (BARC) 298.45p -2.42%Lloyds Banking Group (LLOY) 51.86p -2.41%Aberdeen Asset Management (ADN) 412.10p -2.35%Hargreaves Lansdown (HL.) 685.00p -2.28%CRH (CRH) 1,333.00p -1.48%Morrison (Wm) Supermarkets (MRW) 253.80p -1.36%Bunzl (BNZL) 1,097.00p -1.35%FTSE 250 - Risers3i Group (III) 266.90p +3.09%Investec (INVP) 473.30p +2.87%Rank Group (RNK) 159.20p +2.71%William Hill (WMH) 376.00p +2.62%SVG Capital (SVI) 313.80p +1.55%Betfair Group (BET) 660.00p +1.54%Regus (RGU) 117.40p +1.38%Drax Group (DRX) 593.00p +1.37%JD Sports Fashion (JD.) 750.00p +1.35%Amlin (AML) 379.90p +1.31%FTSE 250 - FallersCOLT Group SA (COLT) 101.00p -5.34%New World Resources A Shares (NWR) 290.80p -4.62%Centamin (DI) (CEY) 53.80p -4.53%Petra Diamonds Ltd.(DI) (PDL) 114.90p -4.25%PZ Cussons (PZC) 379.80p -3.70%Pace (PIC) 216.00p -3.57%Hunting (HTG) 826.00p -3.45%Bumi (BUMI) 330.30p -3.22%Telecity Group (TCY) 855.50p -2.62%Synergy Health (SYR) 1,089.00p -2.59%BC