What's the data horizon?

In FSB Pro I also get a margin call but nothing changes when I slightly change the new units.

I have tested this behavior once again on FSB Pro and it reproduces constantly in same strange way. But it happens only for exact values of parameters as shown here: the starting equity has to be 300€, the leverage has to be 500, the historical data set has to be the one included with FSB Pro – FSB Demo data EURUSD, H1. All other units has to be as those shown in strategy description file.

The strategy takes the starting equity from 300 to around 30000€ under one year time. But when I will change “Initial account” (in  “Account / Account settings”) from 300€ to 301 or to 299 the strategy changes from a superb one to immediate margin call. If “Entry units for a new position” (in Strategy Properties ) will be changed from 3,00 to 3,005  the result always changes to margin call.

But - I tried to run this strategy through Optimizer and I found that the strategy becomes even better, giving at the end of year equity of 35258€ - so some parameters can be changed without ruining the strategy.

I thought that this can be a case extreme curve fitting. But if this strategy is tested under FSB, this behavior will not take place. I wanted to attach here image of the Balance / Equity Charts showing progression from 300€ to 35258€, but I don’t yet know how to insert images – I am rather new to this forum. I will attach here the image file (instead for inserting the image into text)

(Edited: image included in the post by using postimage - rightmost icon in the toolbar)

Mr Popov, thank you for looking at this subject. I am attaching the requested files here.

Everything with the calculations is normal.

The problem is that the position opens very large amount comparing to the initial account value - up to 19 lots.
When the initial account is exactly 300 Eur - the positions pass just below the limits. If you increase the account to 301 Eur. Order No 929 on bar No 563 is canceled because it goes to add 0.88 lots to a position of 19.18 lots - total amount = 20.06, which is above the limit of max 20 lots.

When the initial account is 300 eur, this order is not canceled and FSB sets a new SL/TP. This makes the difference.

Set Account representation in points, if you wan to compare the values easily.