Segars, Alan D. "Performance Dynamics of Screened Corporate Bonds" Working Paper, 2000.

Compares returns of a socially screened bond portfolio with returns for the Lehman Corporate Bond Index for the January 1994-December 1998 time period. Average maturity both the SRI Portfolio and LCB Index was 12.7 years, although the SRI Portfolio had slightly lower overall credit quality. The SRI Portfolio outperformed the LCB Index by 1.98% per year. Of this, 1.74% appeared attributable to earnings drive, while 0.24% was attributed to sector differences. Social screens had "little or no impact on excess returns."