# AverageStatistics A value that encapsulates an average measurement with supporting statistical data. ``` struct AverageStatistics where DimensionType : Dimension ``` ## Discussion `AverageStatistics` provides the average value alongside a sample count and standard deviation. When statistical data is unavailable, `count` is `0` and `standardDeviation` is negative. You encounter `AverageStatistics` as the type of certain metric properties, such as [`value`](/documentation/MetricKit/SuspendedMemoryMetric/value) and [`averageMemory`](/documentation/MetricKit/SignpostIntervalMetric/averageMemory): ```swift let statistics = metric.value // AverageStatistics print(statistics.average) // Measurement print(statistics.count) // Int — number of samples print(statistics.standardDeviation) // Double — negative if unavailable ``` ## Topics ### Statistics [`let average: Measurement`](/documentation/MetricKit/AverageStatistics/average) The average measurement value. [`let count: Int`](/documentation/MetricKit/AverageStatistics/count) The number of samples used to calculate the average. [`let standardDeviation: Double?`](/documentation/MetricKit/AverageStatistics/standardDeviation) The standard deviation of the distribution of values used to calculate the average. ## Relationships ### Conforms To [`Decodable`](/documentation/Swift/Decodable) [`Encodable`](/documentation/Swift/Encodable) [`SendableMetatype`](/documentation/Swift/SendableMetatype) [`Sendable`](/documentation/Swift/Sendable) [`Equatable`](/documentation/Swift/Equatable) [`Hashable`](/documentation/Swift/Hashable) --- 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)