Montana Board of Investments, Helena, may consider investing a small portion of its $2.7 billion domestic equity portfolio in an indexed strategy, said James Penner, chief investment officer. Currently, the board, which oversees $5.5 billion in pension assets, manages the entire U.S. equity portfolio internally. No decision has been made on the size of the portfolio or whether it would be managed internally or externally. "We would start very small and monitor the progress and without any commitment on how far were going and how fast, Mr. Penner said. The board will address the issues in early March.