Data Documentation

After the data have been collected, analyzed, and normalized, they must be documented and archived for future use. One way to keep a large amount of historical data viable is to continually supplement them with new or updated data, such as a new system’s actual costs, new contracts, and updated vendor quotes.

All data collection activities must be documented as to source, work product content, time, units, and assessment of accuracy and reliability. Comprehensive documentation during data collection greatly improves quality and reduces subsequent effort in developing and documenting the cost estimate. The data collection format should serve two purposes. First, the format should provide for the full documentation and capture of information to support the analysis. Second, it should provide for standards that will aid in mapping other forms of cost data.

Previously documented cost estimates may provide useful data for a current estimate. Relying on previous estimates can save the cost estimator valuable time by eliminating the need to research and conduct statistical analyses that have already been conducted. For example, a documented program estimate may provide the results of research on contractor data, identification of significant cost drivers, or actual costs, all of which are valuable to the cost estimator. Properly documented estimates describe the data used to estimate each WBS element, and this information can be used as a good starting point for the new estimate. Moreover, relying on other program estimates can be valuable in understanding various contractors and providing cross-checks for reasonableness.

Thus, previous estimates can provide the cost estimator with valuable data and can also save time because they provide a structure from which to develop the new cost estimate. They also help avoid repeating effort because the cost estimator can leverage off the work of others.