Magic formula investing was derived by Joel Greenblatt, he used it to buy a basket of stocks that has high earning yields and a high return on capital.
Wikipedia has documented the approach and the formula, you can find the link here. Below is the extraction of the para from the link.
The Formula
- Establish a minimum market capitalization (usually greater than $50 million).
- Exclude utility and financial stocks.
- Exclude foreign companies (American Depositary Receipts).
- Determine company's earnings yield = EBIT / enterprise value.
- Determine company's return on capital = EBIT / (net fixed assets + working capital).
- Rank all companies above chosen market capitalization by highest earnings yield and highest return on capital (ranked as percentages).
- Invest in 20–30 highest ranked companies, accumulating 2–3 positions per month over a 12-month period.
- Re-balance portfolio once per year, selling losers one week before the year-mark and ...
