# Time Segments ## Overview **Time Segments** allow a [**Variable** ](/variables/variable-basics.md)to calculate its values differently depending on the period of the [**Model**](/models/home-tab.md).
Shows the preview panel of a Variable with two Time Segments

Example Variable with two Time Segments

For instance, in the example above, the `Monthly price per member` Variable calculates its value using an inflation [**Calculation**](/calculations/introduction-to-calculations.md): `Monthly price per member [-1] * (1 + Price inflation)`. This Variable references the previous period's value of itself (indicated by the `[-1]` part of the Calculation). At the start of the Model, we need to tell the Variable what that value should be, as there are no previous periods to obtain the value from. We do this by creating a new Time Segment for the first period of the Model, which will act as an `Assumption` segment, which we can link to the inputs of the Model. The second Time Segment is an `Auto` segment, meaning it performs the default Calculation of the Variable. The rest of this section explains the various ways of creating and manipulating Time Segments, and the implications of using them. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://help.taglo.io/variables/time-segments.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.