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My secret stock filters for finding bargain value shares

Jon Smith talks through the three filters that he uses to find cheap value stocks to buy, along with how to interpret the different ratios used.

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As retail investing becomes more and more popular, free services and data sharing have also increased. This means that it’s quite easy to filter for value shares using different ratios online. But it still means that an investor needs to knows the screeners to add in. Here are the filters that I use.

What is a stock filter?

A stock filter is simply a way of sifting through the thousands of shares that I could decide to buy. Before I even start, I have to be clear if I’m targeting dividend, value or growth ideas. Once I’ve settled on my aim (in this case value), I can proceed.

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As a disclaimer, all of the ratios used have the goal of providing me with a pool of relevant stocks to choose from. Yet I won’t simply buy without doing any company-specific research. There’s plenty that hard numbers can’t tell me about the state of a sector or the outlook for a business. So it’s important to note that the filters are a supporting guide, not a tool to make a blind purchase.

Two initial ratios

The first filter I use is to screen for ratios related to the share price. One is the price-to-book and another is the price-to-sales.

Both try to assess how the current price compares to either the revenue of a business or the book value. If it’s below a certain benchmark, the stock could be flagged as being undervalued.

The book value of a company refers to the net figure after taking away the liabilities from the assets of a firm. If the book value per share relative to the share price is below 1, it usually means the stock is good value.

If the price-to-sales ratio is below 2, again it could indicate a good purchase. This ratio highlights how much value the market assigns to £1 of revenue.

Watch the debt level

An extra filter I add is the debt-to-equity ratio. I think this is really important when trying to find value stocks. After all, a company might have a low price-to-book and price-to-sales ratio. But what if this is because the firm has very high debt levels? It would render the other two points useless.

A figure of 1 or less is considered good, with anything above 2 being a bit concerning. A low number shows me that borrowings aren’t out of control and shouldn’t materially impact the business going forward.

My end goal

With these three filters, I can aim to eliminate a lot of stocks that don’t fit my agenda. More than that, they should help me to find some bargains to buy. Even though I still need to do research, the screening helps to cut down on my time being wasted by looking at companies that don’t fit my value aim.

Jon Smith has no position in any of the shares mentioned. The Motley Fool UK has no position in any of the shares mentioned. Views expressed on the companies mentioned in this article are those of the writer and therefore may differ from the official recommendations we make in our subscription services such as Share Advisor, Hidden Winners and Pro. Here at The Motley Fool we believe that considering a diverse range of insights makes us better investors.

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