A numeration system associates a unique string, Ξ(n), with each positive integer n, where each string is over the same finite alphabet. Various digit counting statistics of Ξ(n) are of interest with respect to a numeration system. An example is the digital sum, which is the sum of the digits in the number. We present a unifying framework for deriving identities for the generating functions of such statistics in many of the more popular numeration systems.