PT - JOURNAL ARTICLE AU - Andrew W. Lo AU - Pankaj N. Patel TI - 130/30 AID - 10.3905/jpm.2008.701615 DP - 2008 Jan 31 TA - The Journal of Portfolio Management PG - 12--38 VI - 34 IP - 2 4099 - https://pm-research.com/content/34/2/12.short 4100 - https://pm-research.com/content/34/2/12.full AB - Long-only portfolio managers and investors have acknowledged that the long-only constraint is a potentially costly drag on performance, and loosening this constraint can add value, but the extent of the performance drag is difficult to measure without a proper benchmark for a 130/30 portfolio. A passive but dynamic benchmark can be developed, consisting of a plain-vanilla 130/30 strategy using simple factors to rank stocks and standard methods for construction of portfolios based on these rankings. Two types of indexes are produced—investable and look-ahead indexes; the former uses only prior information, and the latter uses realized returns to set an upper bound on performance. Historical simulations of these 130/30 benchmarks illustrate their advantages and disadvantages under various market conditions.TOPICS: Equity portfolio management, accounting and ratio analysis, portfolio theory