Change Polarity or Number Sign

    Sub Change_Number_Sign()
        'This module will change the sign of numbers i.e. (positive to negative) and (negative to positive).
        Dim MyCell As Range
        For Each MyCell In Selection.Cells
            If Not (IsEmpty(MyCell.Value)) And IsNumeric(MyCell.Value) Then
                MyCell.Value = MyCell.Value * (-1)
            End If
        Next
    End Sub