Blue line = DATA. Red line = S&P 500. Tableau Software's share performance over the past month. Can you spot the spike? Source: Motley Fool CAPS.

What: On Wednesday, Feb. 4, data visualization specialist Tableau Software (NYSE:DATA) announced blowout earnings of $0.27 per share in its fiscal fourth quarter. That was better than analysts expected -- 69% more than Tableau had earned a year earlier -- and sales were up 75%. Within hours, analysts at Cantor Fitzgerald, who had already recommended buying the stock, announced that they were lifting their price target on Tableau stock to $150.

Tableau currently costs less than $100 a share, closing Friday at $97.41.

So what: According to ratings aggregator, Cantor is placing a bet that Tableau will deliver on a "strong 2015 outlook." The analyst still assumes that Tableau will lose money in fiscal Q1, mind you, but it's focusing instead on the company's potential to grow revenues past $580 million over the course of the year -- 40% growth over 2014 levels.

Why? Says Cantor: "Not only did revenue and profits reach new record highs at Tableau, but both customer additions and the number of large-sized deals reached new peaks ... [evidencing] the company's growing momentum with information workers around the world."

Now what: Cantor may very well be right about that. However, I'm more concerned with the "momentum" we're seeing in Tableau's share price inflation.

Despite a strong Q4, Tableau still ended the year with only $0.08 in profit per diluted share, which works out to a trailing P/E ratio of 1,218 on the stock. Granted, if we extrapolate the strong momentum shown in Q4 into the future, and assume the company can earn, say, $0.27 every quarter this year (despite Cantor's assuming a Q1 loss), then Tableau's forward P/E ratio would fall to "only" 90.

Even for a stock expecting 44% annualized profits growth over the next five years, that's pretty rich.

Another reason to worry about Tableau, meanwhile, is the analyst recommending it. Cantor Fitzgerald has been right about Tableau over the past few months, no doubt. But we've been monitoring this analyst's performance for far longer than that -- since 2006, in fact. And over that time, our data show Cantor Fitzgerald's recommendations beating the market only 43% of the time. Indeed, across 210 recommendations that it's made public, we clock Cantor's average stock pick as under-performing the market by a half a percentage point.

So if you were looking for a reason to avoid Tableau Software stock -- a reason other than the insanely high price tag, that is -- the fact that Cantor Fitzgerald is recommending it sounds like a pretty good reason to worry, to me.


Even in the Software sector, Cantor's record is a bit mixed. Source: Motley Fool CAPS.