An automated retirement plan manager manages the assets of an employee retirement benefits plan on behalf of an employer. The plan manager executes trades on investment vehicles based on instructions from an automated independent investment advisor. The advisor calculates a human capital for each plan participant based on data derived from the employer and from the participant through an interface, and based on that human capital calculation recommends an allocation of portfolio assets to the participant. This recommendation, once presented for review by and perhaps modified by the participant, becomes an instruction to the plan manager. As the participant ages his or her human capital is recalculated, and this is used to determine whether the participant's present portfolio type should now be switched to a more conservative one.