While the Dow Jones Industrial Average surged toward its best day in three months, volume-weighted market breadth readings suggest investors are buying at a cool, calm and collected pace. The Arms Index, which tends to fall below 1.000 during broad market rallies, as volume in advancing stocks increases at a faster pace than the number of stocks that are rising, is little changed at 0.963 for the NYSE and up slightly at 1.151 on the Nasdaq. Meanwhile, the Dow was up 442 points, or 1.7%, while the Nasdaq Composite shot up 1.9%. Many technicians believe the Arms has to fall to 0.500 or below to suggesting panic-like behavior. The number of advancing stocks outnumbered decliners by a 3.16-to-1 margin on the NYSE and by a 4.02-to-1 score on the Nasdaq, while volume in advancing stocks outnumbered down volume by 3.28 to 1 on the Big Board and by 3.49 to 1 on the Nasdaq.Market Pulse Stories are Rapid-fire, short news bursts on stocks and markets as they move. Visit MarketWatch.com for more information on this news.