Structural health monitoring (SHM) involves gathering data to assess the condition of a structure, often to inform maintenance decisions throughout its life cycle. While the information obtained from an SHM system can enhance decision-making, it is essential to evaluate its overall value by considering the expenses associated with designing, developing, installing, maintaining, and operating the system. Quantifying the value of an SHM system requires pre-posterior cost-benefit analysis. To facilitate the evaluation of an SHM system during the design phase, we propose three time-normalized, unitless value of information (VoI) metrics that can be useful in evaluating the performance of an SHM design over an extended period of time. These metrics are (1) average annual expected rate of savings; (2) compounded annual expected rate of savings; (3) exponentially compounded annual expected rate of savings. We investigate the limiting cases of these metrics and demonstrate their use on a miter gate life cycle management application.