# HistoricalComparison.precipitationAmount(_:) The comparison relates to the amount of precipitation at the location averaged over the past 30 days. ``` case precipitationAmount(Trend) ``` --- Copyright © 2026 Apple Inc. All rights reserved. | [Terms of Use](https://www.apple.com/legal/internet-services/terms/site.html) | [Privacy Policy](https://www.apple.com/privacy/privacy-policy)