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cost performance index (CPI) for the project. CPI is calculated by dividing BCWS / ACWP and multiplying by 100 to express it as a percentage. A CPI of 100% means that the estimated cost was exactly right and the project came in exactly on budget. If it is under 100%, the work cost less effort than planned; a CPI greater than 100% means that the estimate was not adequate for the work involved. CPI can be used either to compare projects or phases within a project.

From

Cover of Applied Software Project Management

Note

CPI defined and introduced