TY - JOUR T1 - The Truth About Diversification by the Numbers JF - The Journal of Investing SP - 93 LP - 95 DO - 10.3905/joi.2000.319444 VL - 9 IS - 4 AU - Ronald J. Surz AU - Mitchell Price Y1 - 2000/11/30 UR - https://pm-research.com/content/9/4/93.abstract N2 - Most of us have heard the statement “90% of available diversification is achieved with a 15-stock portfolio.” Very few, if any, of us behave as though we believe this statement, and there's good reason why—it's not true. This article lays out the truth about how many times it takes to obtain adequate diversification in a domestic equity portfolio. It's much more than 15. ER -