Stuart Reagan, CIO of the $13 billion Kentucky Teachers' Retirement System, Frankfort, will retire at the end of November. Paul Yancey, an in-house fixed-income portfolio manager, will take over as CIO in December, according to Mr. Reagan. Gary L. Harbin, executive secretary, said fund officials will seek another person "to fill out" the system's internal management team, and there will be some reallocation of responsibilities, but no determination has been made. Mr. Reagan said about half of the pension fund's assets are managed internally. The overall asset allocation is 55% equity, 35% fixed income, 7% cash and 3% real estate. Mr. Harbin said the retirement system is "losing a great chief investment officer" with the departure of Mr. Reagan, who became the system's CIO in 1981. He has "done a great job of putting the investment team together," Mr. Harbin said, adding that Mr. Yancey is well versed in the board of trustees' investment policies.