Commission and swap: the two lines most tests leave at zero

[Amanhasnoname]

A common trap: the test is run on data and settings that mimic a wide-spread, commission-free account, then the live account is a raw-spread one that charges commission. Take a charge of 3.5 dollars per lot per side, which varies by broker but is in a typical range. That is 7 dollars round trip per lot, and since a pip on a standard lot is about 10 dollars on a USD-quoted pair, it works out to roughly 0.7 pip. Add the 0.1 to 0.2 pip raw spread and the real cost is well above what many scalpers assume.

Swap matters less for scalpers, but not never. Any position open through the daily rollover collects or pays swap, and the Wednesday charge is often tripled. On some pairs and directions the charge can exceed what a short target earns. Check whether the tester counts rollover crossings at all.

The discipline is reconciliation. Take one live week, export the statement, then rerun that same week in the tester with commission and swap entered. Compare line by line: entries, exits, costs. Differences will point at the assumptions that are wrong.

How close did the test net result land to the live statement once real commission went in?