How to name Excel worksheet based on min-max in column

[Admin]

try

Option Explicit

Sub kTest()
    
    Dim lngMin      As Long
    Dim lngMax      As Long
    
    
    With ActiveSheet
        lngMin = Application.WorksheetFunction.Min(.UsedRange.Columns(3))
        lngMax = Application.WorksheetFunction.Max(.UsedRange.Columns(3))
        If lngMin * lngMax Then
            .Name = Split(.Name)(0) & " " & Format(lngMin, "yy") & "-" & Format(lngMax, "yy")
        End If
    End With
    
End Sub