Earlier this week, the Federal Reserve said in its monthly statement that while growth was still “modest,” it expects the economy will pick up from its current pace. Indeed, on average, economists are expecting the GDP to grow at 2.8% next year, and 3% beyond that. That would be a welcome change from the 1.7% the government just reported that GDP grew in the second quarter of the year.

One group, though, doesn’t seem to be buying all the economic optimism: investors. Yes, the S&P 500 (SPX) is up just over 19%. But the stocks that are rising the most are not the ones that investors typically run to if they are betting on a better economy. Health care stocks, for instance, are normally considered a defensive investment, yet they are the best performing industry group in the index. And in general, the value stocks of the S&P 500 have outperformed growth stocks this year, 20% vs. 17%.

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“I’m not sure enough people are appropriately discounting the potential for growth,” says Jason Trennert, the chief investment officer of investment firm Strategas, who thinks the market can rise from here.

Investors perhaps have a good reason to be worried about growth. First of all, this has been the growthless recovery. Nonetheless, corporations have been able to buck the trend, producing double-digit profit increases despite the weak GDP. But that could be coming to an end.

One of the main drivers of the outsized earnings growth was falling interest rates. That allowed companies to refinance debt they had borrowed a few years ago at lower rates. Then that allowed companies to lower their costs and boost their profits, even if their actual earnings weren’t increasing. But after a number of years of low interest rates, companies have probably refinanced as much of the debt they can. What’s more, with interest rates rising recently, the benefits companies will get from refinancing is falling.

Indeed, profits on average for the companies in the S&P 500 look like they rose just less than 2% in the second quarter vs. a year ago.

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Another sign that investors think growth won’t been that strong is valuations. The S&P 500 is currently trading at just over 15 times this year’s expected earnings. Historically, that’s about average. But it’s not nearly as high as it was back in the 1990s, when the price-to-earnings ratio regularly topped 20, and investors were betting on growth.

“We are talking about is degrees of bullishness at this point,” Josh Brown, an investment advisor with Fusion Analytics, who goes by name @reformedbroker, wrote on Twitter on Thursday. And right now it appears the economists are slightly hotter than the market.