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Forum on trading, automated trading systems and testing trading strategies
Is SWAP correctly calculated in MT4 Strategy Tester?
whroeder1, 2014.05.12 11:13
Testing Features and Limits in MetaTrader 4  MQL4 Articles 

I had never tested a long term strategy before so i never noticed it.
So let me ask you something else, is there any way to convert commissions and swaps form profit in eur/usd/etc (as they are returned by OrderCommision and OrderSwap functions) to p/l in points?
Here is an example (but will differ depending on some factors, for which you will have to change depending on your case):
The number of Pips that your commission ($ per million) represents in the case of GBP/USD and a USD Account Balance can be calculated as follows:
Pip Equivalent = Currency Price * Commission Rate * 2 Operations / 100
For example, if your GBP/USD Price is 1.62012 and your commission is $35 per million, then
Pip Equivalent = 1.62012 * 35 * 2 / 100 = 1.134084 ~ 1.2 pips (after ceiling adjustment)
If your average spread is 0.94 pips and commission is 1.2 pips, then total cost is 2.14 pips average.
EDIT: More details:The "100" has nothing to do with percentage but rather the resultant value after factoring Contract Size and Pip Value for a Standard Lot of volume.
Here is the correct calculation in detail:
Contract Size = 100000 (Standard Lot Contract Size)
Pip Value = $10.00 (for Standard Lot of ???/USD and USD Account Balance)
Currency Price = 1.62012 (example for GBP/USD)
Value = Currency Price x Contract Size = $162012.00
Turnover = Value x 2 (open & close) = $324024.00
Commission Value = $35.00
Commission Scale = $1000000.00 (Million $)
Commission Rate = Commission Value / Commission Scale = 0.000035
Commission per Trade = Turnover x Commission Rate = $11.34084
Commission in Pips = Commission per Trade / Pip Value = 1.134084 pips
Thus the resultant simplified calculation is as follows:
Commission in Pips = Currency Price * Commission Value * 2 / 100
Commission in Pips = Currency Price * Commission Value / 50
EDIT2: However, please note that this is an approximation, as we are using the same Currency Price for both the Open and Close of the Trade. To be exact, we would have to calculate separate commissions for the opening price and closing price, but the resulting difference from the above calculation is negligible. But if you wish, just use the average price between the opening and closing prices, in the calculation, for a better approximation.
Please note that this is only an example and depends on how commission is defined by your broker and in what currency it is expressed.
EDIT: Do a search as well. I found the following:
Forum on trading, automated trading systems and testing trading strategies
How to calculate commission as spread?
Jaume Torne, 2015.07.06 09:15
Another proof why an EA has most of times completely different results on live. Imagine that bug on a live account with real money, easy way to lose your money thinking that it is because a bad robot. No always! Sometimes may be because of a platform bug.
On tester, orders 3 & 4 close with pips gain, but tester give us a negative profit as a result!
Isn't it "wonderful"?