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Translating Cost Models from Excel into ACE: Best Practices and Lessons Learned

Methods & Models Track

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Translating life cycle cost models from Excel into ACE often proves to be a daunting task, especially for analysts who are novice or intermediate-level ACE users. This session will recommend a general approach to the translation process and identify several ACE best practices: combining Dynamic Equation Columns (DECs) and the SumIf( ) function to manage hardware configurations; accessing lookup tables with relative row addressing; and using the OpFieldedUnits( ) function to phase Operations & Maintenance costs. The session will conclude with lessons learned from recent work on the Ship’s Signal Exploitation Equipment Increment F (SSEE(F)) program managed by the Naval Engineering Logistics Office (NELO), in which an Excel cost model with 56 worksheets was translated into a single ACE session with 850 rows and 25 columns. Incorrectly applied inflation turns out to be among the most commonly propagated errors in Excel cost models. When properly used, ACE is a versatile tool that accommodates almost any estimating requirement.


Sam Bresnahan
Sam Bresnahan is a cost analyst at Tecolote Research, Inc. He has five years of experience developing life cycle cost estimates for vehicles, surface assets, communications electronics, information systems, and sensor systems for all major services. His current certifications include SCEA Certified Cost Estimator/Analyst (CCE/A) and Certified ACEIT 7.0 Instructor. Sam holds a B.S. in Chemistry from the University of Virginia (2003).