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# Open

## Definition

A collection of historical bar opening prices.

## Property Value

An **ISeries`\<double\>`** type object. Accessing this property via an index value `[int barsAgo]` returns A **double** value representing the price of the referenced bar.

## Syntax

`Open`

`Open[int barsAgo]`

## Examples

```csharp
//Current bar opening price
double barOpenPrice = Open[0];

// Opening price of 10 bars ago
double barOpenPrice = Open[10];

//Current bar value of a 20 period simple moving average of opening prices
double value = SMA(Open, 20)[0];
```