Magic Formula (Joel Greenblatt)

Joel Greenblatt introduced the Magic Formula in his 2005 book The Little Book That Beats the Market, writing it as an accessible account for non-professional investors. The genius of the framework was its elegant combination of two principles that had been validated separately in academic literature — value (buy cheap) and quality (buy good businesses) — into a single composite rank. The back-tested US results showed that the top decile of Magic Formula stocks significantly outperformed the S&P 500 over a 17-year period, though with multi-year stretches of underperformance that tested holding discipline.

Earnings yield was defined as EBIT (earnings before interest and taxes) divided by enterprise value (market cap plus net debt). Using EBIT rather than net income removed the distortion from varying leverage and tax rates, and using enterprise value rather than market cap standardised across companies with different capital structures. This yielded a capital-structure-neutral measure of how cheaply the market was pricing the company's operating earnings. Return on invested capital was defined as EBIT divided by the sum of net working capital (current assets minus current liabilities, excluding cash and interest-bearing debt) and net fixed assets, measuring how efficiently the business deployed its operating asset base.

Applying the Magic Formula to Indian listed companies required adaptation. In India, EBIT was derived from the profit and loss statement by adding interest and taxes back to profit before tax, or equivalently by taking operating profit and adjusting for other income. Enterprise value required market capitalisation data combined with net debt from the balance sheet. The invested capital calculation needed careful treatment of Indian accounting: working capital items in India sometimes included advances to suppliers or security deposits that were operating in nature but classified differently than in US GAAP.

Backtesting of the Magic Formula on Indian data showed that the combined earnings yield plus ROIC ranking approach had historically outperformed the Nifty 500, though the magnitude of outperformance varied across periods and implementation details. The strategy worked best in the mid-cap and small-cap segments where pricing inefficiencies were greater and the market's ability to immediately reward cheap, high-quality companies was less reliable than in the large-cap space. In large caps, the Magic Formula companies — typically PSU companies with high earnings yields but also high ROIC in their operating segments — were more efficiently priced and offered less excess return opportunity.

Transacting the Magic Formula strategy in India involved specific implementation friction. The top-ranked stocks at any given time often included cyclical businesses with elevated earnings at peak cycle (producing high EBIT yields that would not persist), making it important to use normalised or mid-cycle EBIT rather than latest reported figures. Additionally, financial companies — banks, NBFCs, insurance companies — needed to be excluded or separately handled because the ROIC calculation was not meaningful for leveraged financial intermediaries where borrowed capital was the input rather than the product.

For individual investors in India, the Magic Formula offered a systematic, quantitative framework that removed emotional decision-making from stock selection and enforced both valuation discipline and quality discipline simultaneously. Its practical implementation through tools like Screener.in, which allowed users to filter by EV/EBIT (the reciprocal of earnings yield) and ROCE (a close proxy for Greenblatt's ROIC), made it accessible without requiring sophisticated data terminals.