---
title: throughputKey
framework: foundation
role: symbol
role_heading: Type Property
path: foundation/progressuserinfokey/throughputkey
---

# throughputKey

A key with a corresponding value that indicates the speed of data processing, in bytes per second.

## Declaration

```swift
static let throughputKey: ProgressUserInfoKey
```

## Discussion

Discussion If present, the autogenerated localizedAdditionalDescription uses the value to provide a string that presents more information.

## See Also

### Using General Keys

- [estimatedTimeRemainingKey](foundation/progressuserinfokey/estimatedtimeremainingkey.md)