What is the definition of an index in project management terms?

In project management, the term "index" primarily refers to a ratio that expresses a relationship between two numerical values. By defining an index as a ratio in which one number is divided by another, it provides a means to gauge performance or efficiency relative to a baseline.

For example, various indices, like the Cost Performance Index (CPI) or Schedule Performance Index (SPI), are utilized to assess the performance of a project against its planned budget or schedule. These indices offer insights into whether a project is on track and help project managers make informed decisions based on quantitative measurements.

The other options do not align with the definition of an index in project management. Scheduling resources, representing project scope, or calculating profit margins are distinct project management activities or tools, but they do not encapsulate the concept of an index as a ratio of two values.