Alliant Energy Corporation's (NASDAQ:LNT) price-to-earnings (or "P/E") ratio of 23x might make it look like a sell right now compared to the market in the United States, where around half of the companies have P/E ratios below 16x and even P/E's below 9x are quite common. Nonetheless, we'd need to dig a little deeper to determine if there is a rational basis for the elevated P/E.

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While the market has experienced earnings growth lately, Alliant Energy's earnings have gone into reverse gear, which is not great. One possibility is that the P/E is high because investors think this poor earnings performance will turn the corner. If not, then existing shareholders may be extremely nervous about the viability of the share price.

Check out our latest analysis for Alliant Energy

Keen to find out how analysts think Alliant Energy's future stacks up against the industry? In that case, our free report is a great place to start.

How Is Alliant Energy's Growth Trending?

The only time you'd be truly comfortable seeing a P/E as high as Alliant Energy's is when the company's growth is on track to outshine the market.

Taking a look back first, the company's earnings per share growth last year wasn't something to get excited about as it posted a disappointing decline of 3.2%. This has erased any of its gains during the last three years, with practically no change in EPS being achieved in total. Accordingly, shareholders probably wouldn't have been overly satisfied with the unstable medium-term growth rates.

Looking ahead now, EPS is anticipated to climb by 11% per annum during the coming three years according to the nine analysts following the company. With the market predicted to deliver 11% growth each year, the company is positioned for a comparable earnings result.

With this information, we find it interesting that Alliant Energy is trading at a high P/E compared to the market. Apparently many investors in the company are more bullish than analysts indicate and aren't willing to let go of their stock right now. Although, additional gains will be difficult to achieve as this level of earnings growth is likely to weigh down the share price eventually.

The Bottom Line On Alliant Energy's P/E

It's argued the price-to-earnings ratio is an inferior measure of value within certain industries, but it can be a powerful business sentiment indicator.

We've established that Alliant Energy currently trades on a higher than expected P/E since its forecast growth is only in line with the wider market. Right now we are uncomfortable with the relatively high share price as the predicted future earnings aren't likely to support such positive sentiment for long. Unless these conditions improve, it's challenging to accept these prices as being reasonable.

And what about other risks? Every company has them, and we've spotted 2 warning signs for Alliant Energy (of which 1 doesn't sit too well with us!) you should know about.

It's important to make sure you look for a great company, not just the first idea you come across. So take a peek at this free list of interesting companies with strong recent earnings growth (and a low P/E).

Have feedback on this article? Concerned about the content? Get in touch with us directly. Alternatively, email editorial-team (at) simplywallst.com.This article by Simply Wall St is general in nature. We provide commentary based on historical data and analyst forecasts only using an unbiased methodology and our articles are not intended to be financial advice. It does not constitute a recommendation to buy or sell any stock, and does not take account of your objectives, or your financial situation. We aim to bring you long-term focused analysis driven by fundamental data. Note that our analysis may not factor in the latest price-sensitive company announcements or qualitative material. Simply Wall St has no position in any stocks mentioned.