1. A real-time activity based accounting system for a manufacturing plant having at least one manufacturing process, said accounting system comprising: at least one sub-plant accounting module configurable to receive process data from one or more sensors associated with the manufacturing process; said sub-plant accounting module including computer readable program code for calculating one or more sub-plant accounting measures using the process data; a process historian coupled to at least one of said sub-plant accounting modules; a translation module coupled to said process historian; a production model accounting database configured to receive the accounting measures from said translation module; and an accounting port operatively associated with said production model accounting database, said accounting port being couplable with an accounting module.