View on GitHub

Three Black Crows Strategy

Three Black Crows is the bearish counterpart to Three White Soldiers, consisting of three long down candles after an advance. The pattern suggests that sellers have seized control as each close lands near the session low.

Testing indicates an average annual return of about 178%. It performs best in the stocks market.

This strategy initiates a short position once the third crow appears, expecting momentum to continue lower. It can also be used to exit longs that were opened by other systems if the pattern forms at resistance.

Risk is managed with a tight percent stop above the pattern high, and trades exit if price closes back above that level.

Details

  • Entry Criteria: pattern match
  • Long/Short: Both
  • Exit Criteria: stop-loss or opposite signal
  • Stops: Yes, percent based
  • Default Values:
    • CandleType = 15 minute
    • StopLossPercent = 2 The strategy only sells. The stop lies StopLossPercent above the highest high of the pattern and the position closes when a candle closes above it.
  • Filters:
    • Category: Pattern
    • Direction: Both
    • Indicators: Candlestick
    • Stops: Yes
    • Complexity: Intermediate
    • Timeframe: Intraday
    • Seasonality: No
    • Neural networks: No
    • Divergence: No
    • Risk level: Medium
using System;
using System.Collections.Generic;

using Ecng.Common;

using StockSharp.Algo.Indicators;
using StockSharp.Algo.Strategies;
using StockSharp.BusinessEntities;
using StockSharp.Messages;

namespace StockSharp.Samples.Strategies;

/// <summary>
/// Three Black Crows strategy.
/// While flat it sells after three bearish candles in a row, each closing below the previous close.
/// The stop lies StopLossPercent above the pattern's highest high, and a close beyond it closes the position.
/// </summary>
public class ThreeBlackCrowsStrategy : Strategy
{
	private readonly StrategyParam<decimal> _stopLossPercent;
	private readonly StrategyParam<DataType> _candleType;

	private readonly List<ICandleMessage> _candles = [];
	private decimal _stopPrice;

	/// <summary>
	/// Distance of the stop beyond the pattern, in percent.
	/// </summary>
	public decimal StopLossPercent
	{
		get => _stopLossPercent.Value;
		set => _stopLossPercent.Value = value;
	}

	/// <summary>
	/// Candle type.
	/// </summary>
	public DataType CandleType
	{
		get => _candleType.Value;
		set => _candleType.Value = value;
	}

	/// <summary>
	/// Constructor.
	/// </summary>
	public ThreeBlackCrowsStrategy()
	{
		_stopLossPercent = Param(nameof(StopLossPercent), 2m)
			.SetNotNegative()
			.SetDisplay("Stop Loss %", "Distance of the stop beyond the pattern, in percent", "Risk");

		_candleType = Param(nameof(CandleType), TimeSpan.FromMinutes(15).TimeFrame())
			.SetDisplay("Candle Type", "Type of candles to use", "General");
	}

	/// <inheritdoc />
	public override IEnumerable<(Security sec, DataType dt)> GetWorkingSecurities()
	{
		return [(Security, CandleType)];
	}

	/// <inheritdoc />
	protected override void OnReseted()
	{
		base.OnReseted();
		_candles.Clear();
		_stopPrice = default;
	}

	/// <inheritdoc />
	protected override void OnStarted2(DateTime time)
	{
		base.OnStarted2(time);

		_candles.Clear();
		_stopPrice = default;

		var subscription = SubscribeCandles(CandleType);
		subscription
			.Bind(ProcessCandle)
			.Start();

		var area = CreateChartArea();
		if (area != null)
		{
			DrawCandles(area, subscription);
			DrawOwnTrades(area);
		}
	}

	private void ProcessCandle(ICandleMessage candle)
	{
		if (candle.State != CandleStates.Finished)
			return;

		_candles.Add(candle);

		if (_candles.Count > 3)
			_candles.RemoveAt(0);

		if (!IsFormedAndOnlineAndAllowTrading())
			return;

		if (Position < 0)
		{
			if (candle.ClosePrice >= _stopPrice)
				BuyMarket(-Position);

			return;
		}

		if (Position != 0 || _candles.Count < 3)
			return;

		var c0 = _candles[0];
		var c1 = _candles[1];
		var c2 = _candles[2];

		if (!(c0.ClosePrice < c0.OpenPrice && c1.ClosePrice < c1.OpenPrice && c2.ClosePrice < c2.OpenPrice && c1.ClosePrice < c0.ClosePrice && c2.ClosePrice < c1.ClosePrice))
			return;

		SellMarket(Volume);
		_stopPrice = Math.Max(Math.Max(c0.HighPrice, c1.HighPrice), c2.HighPrice) * (1 + StopLossPercent / 100m);
	}
}