---
title: "-(_:_:)"
framework: foundation
role: symbol
role_heading: Operator
path: "foundation/measurement/-(_:_:)-2nnoy"
---

# -(_:_:)

Subtract two measurements of the same Unit.

## Declaration

```swift
static func - (lhs: Measurement<UnitType>, rhs: Measurement<UnitType>) -> Measurement<UnitType>
```

## Return Value

Return Value A measurement of value lhs.value - rhs.value and unit lhs.unit.

## Discussion

Discussion note: The unit of lhs and rhs must be isEqual.

## See Also

### Operating on a Measurement

- [*(_:_:)](foundation/measurement/*(_:_:)-1d26c.md)
- [*(_:_:)](foundation/measurement/*(_:_:)-5tv8a.md)
- [+(_:_:)](foundation/measurement/+(_:_:)-9lejn.md)
- [+(_:_:)](foundation/measurement/+(_:_:)-4fsbl.md)
- [-(_:_:)](foundation/measurement/-(_:_:)-1a47h.md)
- [/(_:_:)](foundation/measurement/_(_:_:)-98s40.md)
- [/(_:_:)](foundation/measurement/_(_:_:)-71kwk.md)