Attrition rate refers to the gradual reduction in the number of employees or customers over a period of time, typically due to natural causes such as retirement, resignation, or death. It is a measure of the rate at which individuals or groups leave an organization or stop using a product or service, and is often used as an indicator of the overall health and stability of a company or market. A high attrition rate can be a cause for concern, as it can lead to increased costs and decreased productivity, while a low attrition rate may indicate a strong and loyal workforce or customer base.