How to sum one set data from a set of data in another field for charting

[svickery]

I need to sum CountOfOTS_Hist where OTSHist equals late and a count of CountOfOTS_Hist where  OTSHist equals On_Time

I tried sum(if(OTSHist='On_Time',[CountOfOTS_Hist],0)) but it's duplicating everything

DISPO	OTSHist	CountOfOTS_Hist	OTS_History
F1B	Late	9	25-Mar-19
F1B	On_Time	16	25-Mar-19
F2B	Late	4	25-Mar-19
F3B	On_Time	9	25-Mar-19
F4B	Late	8	25-Mar-19
F4B	On_Time	18	25-Mar-19
F7B	Late	7	25-Mar-19
F7B	On_Time	9	25-Mar-19
IC1	Late	2	25-Mar-19
IC1	On_Time	31	25-Mar-19
IC2	Late	15	25-Mar-19
IC2	On_Time	169	25-Mar-19
IC3	Late	4	25-Mar-19
IC3	On_Time	86	25-Mar-19
IC4	Late	6	25-Mar-19
IC4	On_Time	45	25-Mar-19
IC6	Late	47	25-Mar-19
IC6	On_Time	58	25-Mar-19

[Vegar]

Are you certain that you have not duplicated your data in the datamodell? Is your expression correct if you use this expression
sum(CountOfOTS_Hist)
and make a selection in the OTSHist field?

An alternative to If() is to use SET analysis. Try this expression:
sum({<OTSHist={'On_Time'}>}CountOfOTS_Hist)