Ethical Investing Has No Portfolio Performance Cost

摘要

We guide investors in three ethical investment applications by comparing ethically constrained versus unconstrained optimal portfolio methods that force well-behaved weights. With optimal readjustment upon constrained investing, in Sharpe ratio analysis, we find no evidence of a performance cost for sin-free, carbon-free, or Shariah portfolios even though, in the most exacting case, Shariah investing excludes roughly 65% of common shares from security selection. In each case, we identify the specific portfolio adjustments needed to prevent an ethical portfolio performance cost.