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Project Cost Management
PMBOK Guide 葉明導讀
Project Cost Management l 專案成本管理的目標，就是於預算內完成專案工作。流程僅有三項，相對而言，算是比較不複雜的一個知識領域，卻是專案管理者最大的挑戰。 n To complete project within the approved budget n Processes include 1. Cost Estimating 2. Cost Budgeting 3. Cost Control
Life-cycle Costing l 一種評估專案成本的思維，不只著眼於建造成本。 n Consider operation and maintenance costs in making project decisions
Cost Estimating l 成本估算是 估算出完成各項專案活動所需的成本，做為預算編列 (Cost Budgeting) 亦或是報價設定 (Pricing) 的依據。 n Develops an approximation of the costs of the resources needed to complete project activities n Planning Process Group n Tools and Techniques l Analogous estimating l Determine resource cost rate l Bottom-up estimating l Parametric estimating l Project management software l Vendor bid analysis l Reserve analysis l Cost of quality
Analogous Estimating l 類比估算 需要經驗，快速、成本低是其優點，較不精確是其缺點。 n Also called top-down estimating n A form of expert judgment n Uses historical information n Less costly n Less accurate n Gives the project team an understanding of management’s expectations
Bottom-up Estimating l 估算的精確度取決於專案活動或是工作包的規模及複雜程度，通常較小及單純者較易掌握。 n Estimates the cost of individual work package or individual schedule activities with the lowest level of detail n Summarizes or "rolls up" the detailed cost to higher levels for reporting and tracking purposes
Cost Budgeting l 預算編列以建立成本基準線，以便量測專案執行績效，以及規劃資金需求。 n Aggregates the estimated costs of individual activities or work packages to establish a cost baseline n Planning Process Group
Cost Baseline l 專案成本執行績效的量測基準。 n A time-phased budget n Usually displayed in the form of an S-curve n A output of Cost Budgeting n A component of project management plan
Cost Control l 成本控制包括量測、 分析、預測、掌控變異因素、以及變更管制。 n Influences the factors that create cost variances and controls changes to the project budget n Planning Process Group
Cost Performance Index (CPI) l 成本績效指數 n A measure of cost efficiency n How much we are getting for every dollar invested
Schedule Performance Index (SPI) l 時程績效指數 n A measurement of schedule efficiency n How fast the project is progressing compared to the project plan
Earned Value Management (EVM) l 實獲值管理所使用的計算公式說明如下： n Performance Measurement l EV: Earned value (實獲值) l PV: Planned value (計畫值) l AC: Actual cost (實際成本) n Variance Analysis l CV: Cost variance (成本差異) CV = EV – AC l SV: Schedule variance (時程差異) SV = EV – PV n Performance Index l CPI: Cost performance index (成本績效指數) CPI = EV / AC l SPI: Schedule performance index (時程績效指數) SPI = EV / PV n Forecasting l ETC: Estimate to Completion (竣工尚需成本預估) l BAC: Budget at Completion (竣工預算) l EAC: Estimate at Completion (竣工成本預估) n Three cases of ETC 1. ETC: New estimate 2. ETC = (BAC – EVC): Atypical variances 3. ETC = (BAC-EVC) / CPIC: Typical variances XXC: Cumulative XX to date n Three cases of EAC l EAC = ACC + ETC 1. EAC = ACC + ETC: New estimate 2. EAC = ACC + (BAC – EVC): Atypical variances 3. EAC = ACC + (BAC – EVC) / CPIC: Typical variances 有些書會告訴你，還有另一個公式 4. EAC = BAC / CPIC 其實那只是3的簡化，如下 CPIC = EVC / ACC EAC = ACC + (BAC – EVC) / CPIC EAC = EVC / CPIC + (BAC – EVC) / CPIC EAC = BAC / CPIC l 考題常倒過來問ETC，要想到公式4以及 ETC = EAC – ACC l 另一個名詞是Variance at Completion VAC = BAC – EAC
Opportunity Cost l 多個專案進行取捨評估時的成本考量。 n The cost of choosing one project and giving up another
Sunk Cost l 評估專案是否應繼續時的成本考量。 n Expended cost n Should not be considered when deciding whether to continue with a troubled project
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