What is the Altman Z-Score?
- The Altman Z-Score is a formula from 1968 that predicts whether a company will go bankrupt within two years.
- It combines five financial ratios into a single score, with weights chosen by Edward Altman.
- A score above 2.99 means safe, between 1.81 and 2.99 means grey, and below 1.81 means distress.
- The original test was 72% accurate two years out, and later tests hit 80 to 90% one year before failure.
- It works best for public manufacturers and struggles with banks, insurers, and companies with complex balance sheets.
What is the Altman Z-Score?
The Altman Z-Score is a 1968 formula that predicts how likely a company is to go bankrupt within two years by weighing five financial ratios. It is a distress tripwire, one score naming whether a firm is heading toward insolvency.
How does the Altman Z-Score work?
The formula is Z = 1.2X1 + 1.4X2 + 3.3X3 + 0.6X4 + 1.0X5. Each X is a different ratio. Altman tested 66 companies, half already failed. He used discriminant analysis to pick the weights.
X1 is working capital divided by total assets. X2 is retained earnings divided by total assets. X3 is earnings before interest and taxes divided by total assets. Working capital gauges liquidity, retained earnings measure cumulative profit, and EBIT isolates operating performance before financing effects.
X4 is market value of equity divided by total liabilities. X5 is sales divided by total assets. These five ratios cover liquidity, profitability, and how efficiently the company uses its assets. Some analysts recommend excluding intangible assets from total assets for cleaner comparability.
What do the Z-score zones mean?
A score above 2.99 means safe. A score between 1.81 and 2.99 means grey zone, which is a warning. A score below 1.81 means distress zone. That is where bankruptcy prediction gets urgent.
The original test was 72% accurate at predicting bankruptcy two years out. False negatives ran at 6%. In plain terms, the model correctly flagged roughly three of every four eventual failures within that horizon.
Later tests over 31 years showed 80 to 90% accuracy one year before failure. As the failure date draws closer, the model separates failing firms from survivors more cleanly, so predictions made further out carry wider error.
What are the limits of the Altman Z-Score?
The model was built for public manufacturers with over $1 million in assets. It does not work well for banks, insurers, or early-stage companies that still lose money. Negative working capital can be healthy in some industries, like restaurants, so the score can false-alarm. Off-balance-sheet items skew the numbers.
Altman 1968 data came from a different era. Modern markets move faster. Many analysts now use market-based models instead of accounting ratios alone. The Z-score still works as a quick screen.
Scholars have criticized it for being descriptive, not predictive. Failed firms have different ratios, but that does not guarantee the reverse. Ratios alone cannot tell you who will fail next.
Why is it called the Z-Score?
The Z does not stand for a company or for zero risk. In statistics, a z-score shows how far a data point sits from the average. Altman borrowed the term for one composite score: five ratios, one financial distress signal.
Who uses the Altman Z-Score?
Auditors, management accountants, and courts use it. Loan officers use it to screen borrowers. Since 1985 it gained wide acceptance in loan evaluation systems. It is a cheap way to spot financial distress before it turns into insolvency.
What do declining Z-scores signal?
A falling score is its own warning, even before it reaches the distress zone. Audit Analytics flags a Z-Score that drops two years in a row inside the grey zone. Declining scores show deteriorating financial health long before insolvency looks obvious.
Weak scores cost returns too. Research found companies with low Z-Scores underperformed the market by roughly 5 to 6% a year over two decades. Yet far more low-score firms survive than fail, so read the flag as a prompt, not a verdict.
What about non-manufacturers and emerging markets?
Altman later made a version for non-manufacturers. It drops the sales ratio and uses four ratios instead. The formula is Z = 6.56X1 + 3.26X2 + 6.72X3 + 1.05X4. Safe zone is above 2.6, distress is below 1.1.
For emerging markets, Altman added a constant. The formula becomes Z = 3.25 + 6.56X1 + 3.26X2 + 6.72X3 + 1.05X4. The grey zone sits between 1.1 and 2.6. The constant lifts every score upward to account for typically higher market volatility.
Altman made a version for private manufacturers in 1983. They have no traded share price, so the formula swaps market value of equity for book value: Z = 0.717X1 + 0.847X2 + 3.107X3 + 0.42X4 + 0.998X5.
Real-world examples
Bear Stearns had a Z-score of 0.29 in its default year. AIG was at negative 1.03. Lehman Brothers scored 0.06. All three were in the distress zone years before they failed.
Ford Motors scored 1.32 in 2009 and survived. Although that reading sat inside the distress zone, near the 1.1 floor, the company avoided bankruptcy, a reminder that the score flags risk rather than fixing a fate.
The model is not perfect. It flags risk, it does not guarantee outcomes. Use it as one tool among many. Treat a low score as a prompt for deeper due diligence, not a verdict, and pair it with cash flow and market signals before acting.