Sub convmays()
    Set rgColA = Range("a1:z1000")
    Dim rg As Range
    For Each rg In rgColA.Cells
    rg.Value = LCase(rg.Text)
    Next
    End Sub
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    Sub convminus()
    Set rgColA = Range("a1:z100")
    Dim rg As Range
    For Each rg In rgColA.Cells
    rg.Value = UCase(rg.Text)
    Next
    End Sub