Despite an already strong run, Smart Parking Limited (ASX:SPZ) shares have been powering on, with a gain of 28% in the last thirty days. The annual gain comes to 163% following the latest surge, making investors sit up and take notice.

Since its price has surged higher, when almost half of the companies in Australia's Commercial Services industry have price-to-sales ratios (or "P/S") below 1.6x, you may consider Smart Parking as a stock not worth researching with its 5.9x P/S ratio. However, the P/S might be quite high for a reason and it requires further investigation to determine if it's justified.

Check out our latest analysis for Smart Parking

What Does Smart Parking's Recent Performance Look Like?

Smart Parking certainly has been doing a good job lately as it's been growing revenue more than most other companies. It seems that many are expecting the strong revenue performance to persist, which has raised the P/S. However, if this isn't the case, investors might get caught out paying too much for the stock.

If you'd like to see what analysts are forecasting going forward, you should check out our free report on Smart Parking.

Do Revenue Forecasts Match The High P/S Ratio?

The only time you'd be truly comfortable seeing a P/S as steep as Smart Parking's is when the company's growth is on track to outshine the industry decidedly.

If we review the last year of revenue growth, the company posted a terrific increase of 21%. The latest three year period has also seen an excellent 141% overall rise in revenue, aided by its short-term performance. So we can start by confirming that the company has done a great job of growing revenue over that time.

Shifting to the future, estimates from the dual analysts covering the company suggest revenue should grow by 19% per annum over the next three years. That's shaping up to be materially higher than the 5.1% per annum growth forecast for the broader industry.

In light of this, it's understandable that Smart Parking's P/S sits above the majority of other companies. It seems most investors are expecting this strong future growth and are willing to pay more for the stock.

What We Can Learn From Smart Parking's P/S?

Shares in Smart Parking have seen a strong upwards swing lately, which has really helped boost its P/S figure. It's argued the price-to-sales ratio is an inferior measure of value within certain industries, but it can be a powerful business sentiment indicator.

Our look into Smart Parking shows that its P/S ratio remains high on the merit of its strong future revenues. It appears that shareholders are confident in the company's future revenues, which is propping up the P/S. Unless the analysts have really missed the mark, these strong revenue forecasts should keep the share price buoyant.

You should always think about risks. Case in point, we've spotted 1 warning sign for Smart Parking you should be aware of.

Of course, profitable companies with a history of great earnings growth are generally safer bets. So you may wish to see this free collection of other companies that have reasonable P/E ratios and have grown earnings strongly.

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.