Earned Value (EV) is a comprehensive metric used to measure a project's health, progress, and performance. It is the actual value of work accomplished until the present moment, based on the initial estimated cost for the given scope. It helps in understanding how much value a project has generated compared to the costs that have been incurred. EV is a key component of Earned Value Management (EVM), which is crucial for managing the costs and budgets of complex projects effectively.

Planned Value (PV), also known as Budgeted Cost of Work Scheduled (BCWS), represents the estimated value of the scheduled work at any given point in time during the project. It is used as a performance baseline for determining how well a project is progressing in terms of cost, time, and scope. Comparing PV with the actual cost and earned value indicates if the project is on schedule and within the planned budget. PV plays a vital role in EVM, helping project managers track the financial performance and making informed decisions.

Actual Cost (AC), also known as Actual Cost of Work Performed (ACWP), is the total cost incurred for a specific activity or work done during the project. It includes direct costs such as labor and materials, and indirect costs such as overheads and equipment rental. In EVM, AC is compared with EV and PV to determine project performance and identify cost overruns or underruns. Tracking AC accurately and regularly is essential to maintain effective cost control and risk management processes in a project.

Cost Variance (CV) refers to the difference between the earned value and the actual cost of a project at any given time. It is a crucial EVM tool that depicts whether a project is over or under budget. A positive CV signifies that the project is under budget, while a negative CV points to it being over budget. Maintaining suitable CVs helps project managers identify cost overruns, adjust budgets, and realign resources to ensure the project's smooth progress and the attainment of the objectives within the allocated funds.

Estimate at Completion (EAC) is a projection of the total cost of a project at its completion, taking into account both the actual costs incurred so far and the remaining cost estimates. EAC can vary based on assumptions, risks, and the project's current performance. Several formulas can be used to calculate EAC, such as EAC = Actual Cost (AC) + Budget at Completion (BAC) - Earned Value (EV), or EAC = Actual Cost (AC) + (BAC - EV) / Cost Performance Index (CPI). EAC provides project managers with valuable insights into the final cost of a project, enabling them to make informed decisions about budget adjustments, resource allocation, and project risk management.

Estimate to Complete (ETC) is a concept used to forecast the cost required to complete the remaining work in a project. It represents an updated estimate of the project budget based on its current performance and any changes in scope or resources. ETC can be calculated by subtracting the Actual Cost (AC) from the Estimate at Completion (EAC), or by dividing the remaining work (Budget at Completion (BAC) - Earned Value (EV)) by the Cost Performance Index (CPI). Calculating ETC helps project managers determine if the project will finish within the original budget or if additional funds will be required, allowing them to manage the project more effectively and make necessary changes to successfully complete the project.

To-Complete Performance Index (TCPI) is an EVM metric that helps project managers estimate the required future cost efficiency to achieve a specific project goal, like meeting a target budget. The index is calculated by dividing the remaining work (Budget at Completion minus Earned Value) by the remaining budget (Budget at Completion minus Actual Cost), i.e., TCPI = (BAC - EV) / (BAC - AC). A TCPI greater than 1 indicates that the project must perform more efficiently in the future to meet the cost objective, while a TCPI less than 1 implies that the project can afford to be less efficient. By monitoring TCPI, project managers can identify potential issues early and take corrective actions to improve project performance and increase the likelihood of meeting the desired objectives.

Variance at Completion (VAC) is an EVM metric used to forecast the expected difference between the project's final budget (Budget at Completion) and the estimated cost of the project (Estimate at Completion). It is calculated by subtracting the Estimate at Completion (EAC) from the Budget at Completion (BAC), i.e., VAC = BAC - EAC. A positive VAC indicates that the project is expected to be under budget, while a negative VAC suggests that it will be over budget. Project managers can use this measure to anticipate potential cost overruns and take corrective measures, such as adjusting resource allocation or reevaluating project priorities, to better align the project's final costs with the initial budget and increase the project's success.

Budget at Completion (BAC) represents the total approved budget for a project, encompassing all authorized work components, including labor, materials, and other associated costs. It is a baseline value used to monitor and control the project's financial performance throughout its life cycle. Comparing the BAC with Earned Value (EV) and Actual Cost (AC) enables project managers to determine if the project is on track financially, assess risks, and take corrective actions if required. It is crucial to maintain an accurate BAC to facilitate effective cost management and project performance evaluation.

A Control Account (CA) is a management control point in a project where scope, cost, and schedule management converge. It is a consolidated report of multiple subprojects, work packages, and project management processes, helping project managers maintain an organized approach to managing projects. Control Accounts are assigned to specific levels within a Work Breakdown Structure (WBS), with budgets and timelines calculated using the aggregated values of lower-level items. They play a central role in Earned Value Management by providing cost and schedule performance data, streamlining performance tracking, and assisting in decision-making.