Max Week in Month

Hi, andybamber ;

IF you create a column , try it.

No. Country = 
Var _MW = CALCULATE(max(Res[Week Of Month]),ALLEXCEPT(Res,'Res'[Month]))
return 
IF([Week Of Month]=MAXX(FILTER(ALL('Res'),[Month]=EARLIER(Res[Month])),[Week Of Month]),1)

The final output is shown below:

Or you could create a measure.

No. Country_m = 
Var _MW = CALCULATE(max(Res[Week Of Month]),ALLEXCEPT(Res,'Res'[Month]))
return
CALCULATE(COUNT(Res[z_country_key]),FILTER(ALL('Res'),EOMONTH([snaphot_stamp],0)=EOMONTH(MAX('Date_table'[Date]),0)&&[Week Of Month]=MAXX(FILTER(ALL('Res'),[Month]=MAX([Month])),[Week Of Month])&&[z_country_key]=MAX('Res'[z_country_key])))

The final output is shown below:

Best Regards,
Community Support Team_ Yalan Wu
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