With succession planning a hot topic these days, corporate boards pondering whether to invite the company’s current chief executive to stay on the board have something to chew on: It could negatively impact corporate performance, according to a new report from The Conference Board.

Companies that retained former CEOs on boards have relatively lower industry-adjusted stock returns (-1.2 percent) compared with the 2,733 companies where the CEOs continued as chief executives (3.4 percent return), according to the latest TCB Director Notes report, “Retaining Former CEOs on the Board.”