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# KeyReversalDown

## Description

Returns a value of 1 when the current close is less than the prior close and the current high has penetrated the highest high of the last n bars.

## Syntax

`KeyReversalDown(int period)`

`KeyReversalDown(ISeries\<double\> input, int period)`

**Returns default value**

`KeyReversalDown(int period)[int barsAgo]`

`KeyReversalDown(ISeries\<double\> input, int period)[int barsAgo]`

## Return Value

**double;** Accessing this method via an index value **\[int barsAgo]** returns the indicator value of the referenced bar.

## Parameters

| Parameter  | Description                                                                                     |
| ---------- | ----------------------------------------------------------------------------------------------- |
| **input**  | Indicator source data ([Series\<T>](/developer/desktop-sdk/references/common/iseriest/seriest)) |
| **period** | Number of bars used in the calculation                                                          |

## Examples

```csharp
// If we get a reversal over the past 10 bars go short
if (KeyReversalDown(10)[0] == 1)
    EnterShort();
```

## Source Code

You can view this indicator method source code by selecting the menu New > NinjaScript Editor > Indicators within the NinjaTrader Control Center window.