Ohio Public Employees Retirement System, Columbus, is investing in active currency for the first time, allocating $100 million, said spokesman Richard Baker. The $77.6 billion fund decided to move into currency because it could have attractive return potential and uncorrelated diversification potential, thereby serving as a good complement to our overall investment strategy, said Mr. Baker. As many as four firms could be hired to run the money, with funding most likely coming from cash, Mr. Baker said; allocations of existing managers will not be reduced. The timeframe for making selections was not announced. Ennis Knupp & Associates is assisting.