backtesting

 

dear  all

Can any one explain, why we get diffetent results in MQ5 strategy tester results for the same EA with same settings and same time frames at different times

                                            some times huge profit

                                            some time   loss

                                            why ?  

                                                 is it due to change  in history data and

                                                 possibility of ba change in trend  with time

                                           for instance I was ready with an EA based on bullpower oscillator, right from march 2012 for ATC2012,Which showed only profit in strategy tesrer

                                           ,but near sepember 2012 it gave me negative results only  

 

Because expert advisors tend to be overoptiomized for certain time periods?