How to show max bar on bar chart?

[#1]

I am trying to show only the max bar of my bar chart but I am struggling loads. I am using the expression:

sum( If(Program <> 'DETECT STOP', DowntimeDuration))

From this equation, I would need to display only the highest "DowntimeDuration" bar on the actual bar chart, how do I do this? I have tried things like max(sum( If(Program <> 'DETECT STOP', DowntimeDuration))) but that definitely does not work. I obviously have no idea what I am doing.

Program is the name of a list and DETECT STOP is just one variable that is excluded form that list and then the DowntimeDuration is the y-axis.

[MK_QSL]

Using Dimension Limit....

Even though selecting only largest few values the Expression Total in Expression tab will give you full total

while Using Rank & AGGR it will give you only the total of the items selected.

Though you can change it by selection SUM Of ROWS....!!!