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# -=(_:_:)

Subtract a `TimeInterval` from a `Date`.

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

## 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.

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