Stocks ended mixed Monday, wavering between optimism over strong corporate earnings and persistent concerns in the financial sector about regulation and Greece's debt troubles. Consumer and industrial shares buoyed the market as top companies reported stronger earnings than analysts had expected, adding to evidence of a reviving economy. Caterpillar, whose performance is seen as a bellwether, said first-quarter profit rose to $233 million, reversing a $112 million loss in the first quarter of 2009. The company also raised its sales forecast for the full year. The company said that economic conditions were improving, especially in emerging markets, and that it was bolstering production of heavy equipment to meet robust demand from mining and energy companies. Caterpillar forecast a full-year profit of $2.50 to $3.25 a share, while Wall Street analysts had forecast a profit of $2.69 a share. Its shares rose $2.87, or 4.2 percent, to close at $71.65. 'Some market observers are hoping it is just the tip of the iceberg for the market for another great week,' said M. Jake Dollarhide, chief executive of Longbow Asset Management. 'With Caterpillar getting the week started off on such a good note, there is a lot of positive speculation that the beat will go on.' Other major companies reporting results this week included Exxon Mobil, the Ford Motor Co. and UPS. The appliance maker Whirlpool also helped market sentiment concerning consumer spending on big-ticket items. The company posted first-quarter profit of $164 million on revenue of $4.27 billion, up from $3.57 billion a year earlier. Its shares rose $10.20, or 10 percent, to $112.42. The Dow Jones industrial average rose 0.75 points, or 0.01 percent, to 11,205.03. The Standard & Poor's 500-stock index fell 5.23 points, or 0.43 percent, to 1,212.05, while the Nasdaq composite index fell 7.20 points, or 0.28 percent, to 2,522.95. Uncertainty about a possible bailout of Greece continued as the country negotiated with the International Monetary Fund and the European Union on a huge aid package. Investors were concerned that even with help, the country would have to restructure its debts, and its borrowing costs continued to climb. Confidence in Greek assets sank to a new low as Chancellor Angela Merkel of Germany kept up the pressure, insisting on tougher austerity measures for Greece. In addition, there is uncertainty over when and how the international aid package of up to $60 billion might be delivered. But European markets closed higher. On Wall Street, financial shares weighed on the market. Citigroup said the Treasury had authorized the sale of 1.5 billion of the 7.7 billion shares it holds in the company. 'The Treasury is taking advantage of favorable market conditions to peel off some of their holdings and hopefully make some money for the taxpayer at least,' said Dan Greenhaus, chief economic strategist at Miller Tabak & Co. 'It has been talked about for some time now, so I don't know if it is any great big shock.' Citigroup's shares fell 5.1 percent, to $4.61. Dollarhide said the government's sale plans could be seen as a vote of confidence in Citigroup, and as a positive for financial institutions. But the sector moved lower on Monday as Congress continued to discuss an overhaul of industry regulations. Goldman Sachs was down 3.41 percent, at $152.03, and Bank of America was 2.1 percent lower, at $18.05. The Treasury's 10-year note rose 1/32, to 98 17/32. The yield, at 3.81 percent, was unchanged from late Friday. 