Jobless claims are expected to rise slightly from last week, to 320,000, when they are reported at 8:30 a.m. ET. Trade data are also expected at 8:30 a.m., and ISM nonmanufacturing data are set to be released at 10 a.m. ISM will be especially watched for what it says about service sector hiring.
"I think the economy is getting better. I think today's number was mostly about a rebound to the trend we were on before the winter," said John Ryding, chief economist of RDQ Economics.
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"Claims numbers are very low," Ryding said. "I think the message is very clear. Layoffs are very low. They are at expansion norms. Not many people are being laid off but that's not the part of the labor market that's not functioning. The part of the labor market that's not functioning is fitting the unemployed into the job market."
The Dow on Wednesday rose 40 to 16,573, just 3 points shy of its record, and the S&P 500 climbed 5 points to 1,890, its eighth record close this year. The Nasdaq gained 8 to 4,276. The S&P 400 midcap index and the Dow Transports both hit new all-time highs.
"For right now, I think it still pays to be cautiously bullish, and it's possible fundamentals catch up with the market," said Jack Ablin, CIO of BMO Private Bank. "It's a funny market but from what I see, there's a couple of warning signs but not too many danger signals."
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Ablin said high valuations and a turn in geopolitical events would be the types of things that could make the market stumble.
"To the extent that March weather was better than February, are we going to see better numbers as a result?" Ablin said. "We're seeing a lot of business really has been pushed back. Right now, analysts expectations for Q1 are so meager but for the rest of the year, they're pretty robust."