Longtime stock bull Jeremy Siegel told CNBC on Tuesday that he sees favorable market trends—including the prospect for solid economic growth with low inflation—that could send the Dow Jones Industrial Average past the 20,000 level by the end 2015.
"There are a number of goods things, I think, that need to happen, but certainly that would be even conservative for fair market value if we get some of these favorable trends coming together over this next year," the Wharton School finance professor said on "Squawk Box."
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He cited economic growth of 3 percent to 4 percent, low inflation, cheap gas prices and an improving job market as some of the factors that could help push stocks higher.
But he said, "The 3 percent [GDP], that's the wild card." He cautioned that many forecasters are calling for growth of 2 percent to 2.5 percent in the fourth quarter.
During the October selloff, Siegel had started to waver a bit on whether his prediction of Dow 18,000 by year-end would come to pass. But with the market back on track, he told CNBC earlier this month that he's again confident that blue chips would reach that level after all.