"What's going to be important to us is ultimately management saying, 'we're not seeing the same slide,'" said Mark Luschini, chief investment strategist at Janney Montgomery. "I think that's what you've got to listen for. Otherwise, I don't know what breaks this market out of its trading range of (S&P 500) 1830/1840 or the highs of 1880/1890."
Luschini said he expected the S&P 500 to head toward 1800 when it broke 1840 last week: "There's some weak support there, and you start to get support in the 1760 range. I'm not bought in to today's rally."
Economic data could also be a factor, after the best retail sales gain in 18 months Monday helped fire up the rally that started with Citigroup. Both earnings and economic data are being scrutinized to see how much first-quarter sluggishness can be attributed to weather impact.
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Stocks finished Monday sharply higher, with the Dow up 146 points at 16,173, the S&P 500 up 14 points at 1830, and the Nasdaq up 22 points at 4022. Traders watched developments surrounding Ukraine, and stocks moved higher even though anxiety about the tense situation with Russia sent buyers into gold and oil.
On Tuesday, there is CPI consumer inflation data and the Empire State survey, both at 8:30 a.m. The National Association of Home Builders survey and Treasury data on international capital flows are released at 10 a.m.
"I'm not expecting much in the way of CPI to alter the view that there is none (inflation), and no need for the [Federal Reserve] to do anything heroic," said Luschini. He's watching the Empire State survey for a snapshot of the manufacturing economy.
But Peter Boockvar, chief market analyst at Lindsey Group, said even a blip higher in the consumer price index could give markets a jolt.
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"I think it is a big deal. We've had multiple data points pointing to a bottoming in inflation," said Boockvar. He noted the surprise 0.5 percent jump in the producer price index (PPI) last week. The March number was the largest since June, 2013, due to an increase in food and trade services prices. PPI was down 0.1 percent in February.
He added that a jump in compensation reported by the National Federation of Independent Businesses in its monthly survey could also be a telltale sign. According to the survey, 25 percent of employers reported raising compensation and two percent reported cutting it, the highest number boosting compensation since 2008.