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Entire order not executing

I notice that when I test my algorithm with a small amount of money (~$1,000), the algorithm works well and performs great. However, when I try to run a backtest with ~$100,000, the returns are significantly worse. I notice that the entire order (e.g., sell all shares) does not execute at once. Is there a reason why I can't buy/sell large amounts of stock at once?

1 response

By default, backtests use the VolumeShareSlippage model, in which you can buy or sell no more than 25% of the volume in a bar. See the Help page for details and alternatives.