Adding a column to count rows associated with specific criteria

Hi JenWilson ,

According to your description, here are my steps you can follow as a solution.

(1) My test data is the same as yours.

(2) We can create a measure.

count of error outcomes = COUNTROWS(FILTER(ALLSELECTED('Table'),'Table'[EE #]=MAX('Table'[EE #]) && 'Table'[order #]=MAX('Table'[order #]) && 'Table'[Error Outcom]=MAX('Table'[Error Outcom])))

(3)We can create a table.

Table 2 = SUMMARIZE('Table','Table'[Name],'Table'[Error Outcom],'Table'[Error Outcome as #],'Table'[EE #],'Table'[order #],"count of error outcomes",[count of error outcomes])

(4) Then the result is as follows.

Best Regards,

Neeko Tang

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Thank you so much. This worked just as I requested!