  Software project management is an interpolation of project planning, project
monitoring and project termination. The substratal goals of planning are to
scout for the future, to diagnose the attributes that are essentially done for
the consummation of the project successfully, animate the scheduling and
allocate resources for the attributes. Software cost estimation is a vital role
in preeminent software project decisions such as resource allocation and
bidding. This paper articulates the conventional overview of software cost
estimation modus operandi available. The cost, effort estimates of software
projects done by the various companies are congregated, the results are
segregated with the present cost models and the MRE (Mean Relative Error) is
enumerated. We have administered the historical data to COCOMO 81, COCOMOII
model and identified that the stellar predicament is that no cost model gives
the exact estimate of a software project.
