Method
Cost Guides begins with the practical decision a reader is trying to understand, defines the cost concepts involved, checks formulas against authoritative guidance and explains limitations. Examples use invented numbers and do not represent a market quote.
Primary public references
- U.S. Government Accountability Office — Cost Estimating and Assessment Guide, which presents best practices for developing reliable cost estimates and managing cost with earned value.
- NASA Cost Estimating Handbook, a guide to cost estimating and analysis.
- NASA Cost Estimating and Analysis Overview, including discussion of cost risk, alternatives and resource decisions.
- U.S. Department of Energy — Building Life Cycle Cost Programs, explaining comparison of higher initial cost and lower operating cost alternatives.
- U.S. Department of Energy Project Management Lexicon for selected project-management and cost terminology.
Calculator conventions
Calculators use straightforward formulas stated on or near each tool. Currency formatting is a display convenience only. The lifecycle tool assumes year-end level recurring costs. The PERT tool is a simplified three-point calculation, not Monte Carlo simulation. The earned-value forecast uses BAC divided by CPI and should be compared with a bottom-up forecast.
Limitations
Public guidance developed for government programs may use governance, terminology or thresholds that do not apply to a private or smaller project. Readers should adapt principles rather than copy requirements without context.