Bull market problem: Disappearing sales growth

A trader works on the floor of the New York Stock Exchange.
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Can the bull market continue if companies aren't growing their top line?

That's the question investors thinking about buying stocks need to ask themselves as the latest figures show analysts forecasting little revenue growth for 2015.

This leaves cost-cutting, buybacks and multiple expansion as the only ways for the market to drive returns this year as the strong dollar, collapse in commodity prices and weak overseas demand eats away at the top line.

The technology sector may outperform as it bucks these sales-growth woes by making a run at a double-digit revenue increase this year.