# Shiller PE Ratio The **Shiller PE Ratio**, often referred to as the Cyclically Adjusted Price-to-Earnings (CAPE) ratio, is a world-renowned valuation metric developed by Nobel Prime-winning economist Robert Shiller. Unlike standard PE ratios that can be skewed by temporary earnings fluctuations, the Shiller PE utilizes inflation-adjusted earnings data from the past ten years to provide a smoothed "cyclically adjusted" view of market value. This tool is essential for long-term investors looking to identify historic bubbles, generational buying opportunities, and major regime shifts by quantifying exactly how far the market has stretched from its long-term historical mean. --- # 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/market-valuation-and-on-chain/shiller-pe-ratio.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.