What is Piotroski F-Score?

What is Piotroski F-Score?

The Piotroski F-Score is a nine-point screen that measures a company's financial health. It uses nine criteria split into profitability, leverage liquidity, and operating efficiency. The score separates the strong financials from the weak, helping you pick value stocks.

Joseph Piotroski, then an accounting professor at the University of Chicago, detailed it in a 2000 paper. He wanted to find value stocks that would beat the market. The score runs from 0 to 9. Nine is the best, zero the worst.

You calculate it from a company's financial statements. Each of the nine criteria gets one point if met. Add them up to get the score, which ranges between zero and nine.

How does the Piotroski F-Score work?

The nine criteria fall into three buckets. Profitability holds four: a positive return on assets, positive operating cash flow, rising return on assets from the prior year, and cash flow that exceeds net income.

Leverage liquidity and source of funds holds three: falling long-term debt, a rising current ratio, and no new share issuance. Operating efficiency holds two: a higher gross margin and higher asset turnover.

The score leans on cash flow on purpose. Net income can be dressed up with accounting choices, but cash is harder to fake. A firm whose operating cash flow exceeds its net income is showing earnings backed by real cash, not just write-offs or accruals.

For each criterion, you compare this year to last year. If the condition is true, you get one point. If not, zero. The total is the sum of the nine criteria, giving a single health score.

What does a worked Piotroski F-Score example look like?

Take a company with net income of $323 million, a 4.7 percent return on assets, and $696 million of operating cash flow above net income. That is four profitability points. Long-term debt falls from $120 million to $110 million and no new shares were issued, so two more land.

The remaining three tests fail. The current ratio dips from 2.0 to 1.7, gross margin slides from 31.8 percent to 28.9 percent, and asset turnover drops from 1.54 to 1.11. Three zeros. One point per criterion met, summed across all nine, leaves the company at 6 of 9.

What do the scores mean?

Scores of 8 or 9 mean strong financial health. Scores of 0 to 2 mean weak. Middle scores are average, neither clearly safe nor clearly troubled, and most companies land there.

Higher scores tend to predict better stock returns. Piotroski's research showed this. But don't rely on it alone; treat it as just one input among several in your final decision.

Different industries have different average scores. Compare companies within the same sector. A score of 6 in banking might be strong, but weak in tech, so always judge the number against its sector peers.

Piotroski tested the score on value stocks from 1976 to 1996. He found 57 percent of cheap stocks underperform the market, but strong F-Scores lifted a low price-to-book portfolio by about 7.5 percent a year. The outperformance is largest in small-cap value stocks where analyst coverage is thinnest.

What are the limits of the Piotroski F-Score?

The score only compares one year to the previous year. That misses long-term trends. Cyclical industries can mislead you, because a single good year may not reflect the company's steadier average.

It also ignores market conditions. A pandemic or recession can hit all companies at once. The score won't catch that, since it looks only at each firm's own past numbers. The F-Score does not apply to banks, insurers, and REITs, whose balance sheets make its tests misleading.

Micro-cap stocks often have volatile metrics. The score may unfairly punish them. Use it with caution there, where a small one-off charge can swing the result from strong to weak.

How can you use the Piotroski F-Score?

Use it as a screen to filter value stocks. Start with a list of cheap stocks. Then apply the F-Score to find the strongest, using the score to rank which cheap names look healthiest.

Combine it with other tools like the Altman Z-score. That checks bankruptcy risk. The F-Score checks financial health, so together the two give both a solvency and a quality read.

Treat it as a basket tool, not a single-stock oracle. Screen a large pool of cheap names, keep the 8 and 9 scores, and hold them as a group. One weak pick is survivable, but a diversified set leans on the historical odds working in your favor.

Re-run the score each year. Financial health shifts with every report. A firm that was a 9 last spring can slip to a 4 by autumn, so refresh the count to keep the strongest names in and let the weakened ones go.