# Period ROI Performance over a fixed window answers a simple question: “How much are we up or down since X?” **CandelaCharts – Period ROI** makes that answer immediate by plotting the percent change between today’s daily close and the daily close from a chosen period (1M/3M/6M/1Y or custom days). It keeps the reference on a daily series so your read is consistent across chart timeframes, colors positive vs. negative regimes, and can label the latest value for quick comparisons. --- # 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://docs.candelacharts.com/investing/risk-and-portfolio-management/period-roi.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.