1. An apparatus comprising an error-correction decoder for recovering an error-correction-encoded codeword, the error-correction decoder comprising an extrinsic value generator adapted to: (a) generate a current extrinsic value based on at least one check-node value, wherein the current extrinsic value corresponds to a bit of the error-correction-encoded codeword; and (b) generate a current average extrinsic value based on the current extrinsic value and at least one previous extrinsic value, wherein the current average extrinsic value and the at least one previous extrinsic value correspond to the bit of the error-correction-encoded codeword.