=МАКС(А1:C1)-МИН(А1:C1)

let
    Source = Excel.CurrentWorkbook(){[Name="Table1"]}[Content],
    #"Unpivoted Other Columns" = Table.UnpivotOtherColumns(Source, {"Column1"}, "Attribute", "Value"),
    #"Removed Columns" = Table.RemoveColumns(#"Unpivoted Other Columns",{"Attribute"}),
    #"Grouped Rows" = Table.Group(#"Removed Columns", {"Column1"}, {{"max", each List.Max([Value]), type number}, {"min", each List.Min([Value]), type number}}),
    #"Added Custom" = Table.AddColumn(#"Grouped Rows", "Custom", each [max]-[min]),
    #"Removed Other Columns" = Table.SelectColumns(#"Added Custom",{"Custom"})
in
    #"Removed Other Columns"