Chicago Park Employees Annuity & Benefit Fund trustees voted today to invest $36 million in a J.P. Morgan enhanced stock index fund. The other finalist in the search was A I M Advisors. The move is part of the $600 million funds efforts to eventually have about 20% of the total equity allocation in enhanced index strategies, said Joseph Fratto, executive director. Initial funding will come from a terminated plain vanilla S&P 500 indexed portfolio managed by Northern Trust. Additional allocations will be made from cash flow, Mr. Fratto said.