---
title: "-=(_:_:)"
framework: foundation
role: symbol
role_heading: Operator
path: "foundation/date/-=(_:_:)"
---

# -=(_:_:)

Subtract a TimeInterval from a Date.

## Declaration

```swift
static func -= (lhs: inout Date, rhs: TimeInterval)
```

## Discussion

Discussion warning: This only adjusts an absolute value. If you wish to add calendrical concepts like hours, days, months then you must use a Calendar. That will take into account complexities like daylight saving time, months with different numbers of days, and more.

## See Also

### Adding or Subtracting a Time Interval

- [addTimeInterval(_:)](foundation/date/addtimeinterval(_:).md)
- [addingTimeInterval(_:)](foundation/date/addingtimeinterval(_:).md)
- [advanced(by:)](foundation/date/advanced(by:).md)
- [+(_:_:)](foundation/date/+(_:_:).md)
- [+=(_:_:)](foundation/date/+=(_:_:).md)
- [-(_:_:)](foundation/date/-(_:_:).md)