Hi @Anonymous ,
Please try:
AddColumns(
AddColumns(
GroupBy(
AddColumns(HiddenMasterGallery.AllItems,"NewLabel",If(HiddenCategory="specific item","specific item","Others")),
"NewLabel",
"_cat"
),
"_total",CountRows(HiddenMasterGallery.AllItems),
"_number",CountRows(_cat)
),
"_percentage",
If(NewLabel="specific item",Text((_number/_total)*100,"0%"),"others")
)
Best Regards,
Bof