---
title: "readAttributeApproximateEVEfficiency(completion:)"
framework: matter
role: symbol
role_heading: Instance Method
path: "matter/mtrbaseclusterenergyevse/readattributeapproximateevefficiency(completion:)"
---

# readAttributeApproximateEVEfficiency(completion:)

## Declaration

```swift
func readAttributeApproximateEVEfficiency(completion: @escaping @Sendable (NSNumber?, (any Error)?) -> Void)
```

```swift
func readAttributeApproximateEVEfficiency() async throws -> NSNumber
```