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Return Period Calculator

Related Topics

  • Risk Communication & Perception

A 100-year flood doesn’t only happen once per century. So why is it called that? Use this tool to see the likelihood of experiencing an extreme hazard event in any given year. You can test out different time frames and a range of return periods.

Organization: Understanding Risk and the Global Facility for Disaster Reduction and Recovery (GFDRR)

Learn more: Return Period Calculator

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