Commission

Commission - A fee charged by a broker for executing trades. In forex backtesting, commissions should be factored in as they can impact net performance. Commissions are typically a fixed cost per trade or a percentage of the trade’s value, representing one component of transaction costs that reduce overall returns. (E.g., if a broker charges $7 per lot round-turn, every trade’s profit in the backtest should be reduced by that amount to reflect reality).