Wilk, Richard T. "The Boston South Africa Free (SAFE) Index," in Kinder, Peter, Steven Lydenberg, and Amy Domini, ed., The Social Investment Almanac, New York: Holt, 1992.

Reports on the performance of the Boston SAFE Index, which underperformed the S&P 500 each year from 1986 - 1990, with a beta of 1.0. Finds that "the strong performance of drug stocks over this period represented the greatest challenge to managers of divested portfolios. Not only did drug stocks perform well, but there were few alternatives, because most of this group is restricted." No attempt was made to redress factor exposures created by the South Africa screen.