Determine topN

elizabethvieira , Try using below DAX

Top5Areas =
TOPN(
5,
SUMMARIZE(
'impact (2)',
'impact (2)'[area],
"Total Articles", COUNT('impact (2)'[UT])
),
[Total Articles],
DESC
)

Let's try different approach

First create a measure 

hello elizabethvieira 

the TOPN from your link looks fine. I tried making an example and the result is good.

Left one is total sum and right one is sum of top 5 (exclude E and G as the lowest 2).

also, if you want to show sum of top 5 in pie chart, you can do easier in visual filter as there is no calculation.

before visual filter

after visual filter (put your areas in Legend and your value in Values, then your value again in By Value in visual filter option). in here, change from SUM to COUNT if you want to have count result.

Hope this will help.

Thank you.

Hi elizabethvieira 

Thanks to Irwan and bhanu_gautam  for the quick reply and solution. The link you provided to the pbix file has privacy I can't open it. Here is my test data:

(1) We can create measures.

Count = COUNT('impact (2)'[UT])

Index = 
var _table=SUMMARIZE(ALLSELECTED('impact (2)'),[area],"count",[Count])
RETURN RANKX(_table,[count],,DESC)

(2) We can create tables.

TopAreas = 
   TOPN(
       5,
       SUMMARIZE(
           'impact (2)',
           'impact (2)'[area],
           "PublicationCount", [Count]
       ),
       [PublicationCount],
       DESC
   )

TopAreas2 = 
var _table=SUMMARIZE('impact (2)',[area],"count",[Count],"index",[Index])
RETURN SELECTCOLUMNS(FILTER(_table,[index]<=5),[area],[count])

Best Regards,

Neeko Tang

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