To better understand the concept of a Process Performance Model (PPM), it helps to have a little background about both Process Performance Baselines (PPBs) and PPMs. Both are based on the historical process data that the organization has been collected and analyzing. The CMMI definition of a PPB is a documented characterization of the actual results achieved by following a process, which is used as a benchmark for comparing actual process performance against expected process performance. In other words, the historical process data, when analyzed, will indicate how the process has behaved in the past and the expected range of the process performance. We can able the predict the productivity, defects etc.