---
id: "T:cAlgo.API.BacktestingProgressChangedEventArgs"
kind: "class"
namespace: "cAlgo.API"
url: "https://help.ctrader.com/ctrader-algo/references/Plugin/Backtesting/BacktestingProgressChangedEventArgs/"
---

> Documentation index for agents: https://help.ctrader.com/ctrader-algo/llms.txt · machine index: https://help.ctrader.com/ctrader-algo/api.json

# BacktestingProgressChangedEventArgs (class)

Provides data for the backtesting progress changed event.

Environments: Desktop supported · CLI not supported · Cloud not supported.

- CLI: Available to plugins only, and plugins cannot run in the CLI.
- Cloud: Available to plugins only, and plugins cannot run in the cloud.

## Definition

```csharp
public class BacktestingProgressChangedEventArgs
```

## Examples

C#:

```csharp
protected override void OnStart()
{
    Backtesting.ProgressChanged += OnBacktestingProgressChanged;
}

private void OnBacktestingProgressChanged(BacktestingProgressChangedEventArgs args)
{
    Print("{0:F1}% {1}, completed: {2}", args.Progress, args.Operation, args.Process.IsCompleted);
}
```

Python:

```python
def on_start(self):
    api.Backtesting.ProgressChanged += self.on_backtesting_progress_changed

def on_backtesting_progress_changed(self, args):
    api.Print(f"{args.Progress:.1f}% {args.Operation}, completed: {args.Process.IsCompleted}")
```

## Properties

- `public string Operation {get;}` — Gets the description of the current operation. [details](https://help.ctrader.com/ctrader-algo/references/Plugin/Backtesting/BacktestingProgressChangedEventArgs/Operation/index.md)
- `public BacktestingProcess Process {get;}` — Gets the backtesting process that reported progress. [details](https://help.ctrader.com/ctrader-algo/references/Plugin/Backtesting/BacktestingProgressChangedEventArgs/Process/index.md)
- `public double Progress {get;}` — Gets the progress percentage of the backtesting process. [details](https://help.ctrader.com/ctrader-algo/references/Plugin/Backtesting/BacktestingProgressChangedEventArgs/Progress/index.md)