The present disclosure relates to modeling the transient current of a partially simulated hierarchical gate-level electronic design. Embodiments may include providing a partially simulated hierarchical gate-level electronic design, wherein the design includes a design hierarchy having one or more leaf blocks associated therewith. Embodiments may also include identifying activity of sequential elements of the leaf blocks using simulation vectors, wherein the activity is used to estimate an amount of current associated with the sequential elements. Embodiments may further include computing an adaptive activity of a parent block of the leaf blocks, wherein the adaptive activity of the parent block corresponds to a weighted average of known activity of leaf blocks. Embodiments may also include generating an adaptive activity of a top block of the leaf blocks based upon the adaptive activity of the parent block and performing a mixed-mode simulation based upon the adaptive activity of the top block.