City of Flint (Mich.) Employees Retirement System narrowed a search for its first S&P 500 index manager to three finalists and is expected to make a decision at its March 16 board meeting, said Lisa Dedolph, retirement supervisor for the $750 million fund. The finalists are: Bankers Trust; Northern Trust; and State Street Global Advisors. Diversification is the reason for the search. Portfolio size and funding source are undetermined. Callan Associates is assisting.