hi could anyone help me please. i have the following problem: in the ref() formula one must use only constant data i.e. ref([censored],-1) or ref([censored], lastvalue(aaa) ) what should i do when i want to use different values for every bar i.e. a:=calculated value for each bar; ref([censored],-a) i cannot use ref([censored],lastvalue(a) ) beacause then only the last value is inserted into the ref() formula, but i need different values for every bar . i.e i want to calculate : (present value of the indicator) - (value of the indicator "a" periods ago) and "a" is different for every bar (it is calculated exclusively for each bar) thank you for your help

eHour:=Input("enter the hour",0,24,8); eDate:=Input("Enter the Date-DD",1,31,15); eMonth:=Input("Enter the Month-MM",1,12,4); eYear:=Input("Enter the Year-YYYY",0,2100,2005); numdays:=BarsSince(DayOfMonth()=eDate AND Month() =eMonth AND Year()=eYear AND Hour()=eHour ); vold:=Input("enter volume",0,99999999999,20000); cumpv:=Cum(MP()*V); cumvol:=Cum(V); basecumvol:=ValueWhen(1, numdays=0, cumvol); sr1:=cumvol-basecumvol; a:=valuewhen(1,numdays>0,Round(numdays*(sr1/vold)) ); this is how i determin "a" periods then i want to know what is the value of "cumpv" "a" periods ago when i use lastvalue(a) metastock uses only the last value of "a" in data array. when i use the patrick's formula , the one you can finde above, it returns only one value ( for the last bar) not the curve (values for the specified range of bars).