Earned Value Management API

Earned Value Management (EVM) maths as an API, computed locally and deterministically — the project cost-and-schedule controls used in PMP, PRINCE2 and government contracting. The metrics endpoint takes the budget at completion (BAC), planned value (PV), earned value (EV) and actual cost (AC) — or a percent-complete and planned-percent of BAC — and returns the cost variance (CV = EV−AC), schedule variance (SV = EV−PV), the cost and schedule performance indices (CPI = EV/AC, SPI = EV/PV), the percent complete and spent, and a plain-language over/under-budget and ahead/behind-schedule read. The forecast endpoint projects the finish: the estimate at completion by three standard methods (BAC/CPI when the cost trend continues, AC + remaining budget, and the cost-and-schedule AC + (BAC−EV)/(CPI·SPI)), the estimate to complete (ETC), the variance at completion (VAC) and the to-complete performance index (TCPI) to land on either the original budget or the EAC. A CPI of 0.875 on a 1000 budget forecasts a 1143 overrun. Everything is computed locally and deterministically, so it is instant and private. Ideal for project-management, PMO, construction, aerospace and contracting app developers, project dashboards and earned-value reporting tools, and PMP/PRINCE2 training. Pure local computation — no key, no third-party service, instant. Live, nothing stored. 2 compute endpoints. This is earned-value project control; for loan or NPV cash-flow maths use a finance API.