Sub ForNext()
    
    Dim i As Integer
    Dim N As Integer
    Dim Total As Integer
    
    Range("C5").ClearContents
    Range("C6:C19").ClearContents
    
    For i = 6 To 19
    
       N = Range("B" & i) * Range("D5")
    
       Range("C" & i).Value = N
       Total = Total + N
       Range("C5").Value = Total
    
    Next
    
End Sub
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Sub ForNext2()
    
    Dim intRow As Integer
    Dim i As Integer
    Dim N As Integer
    Dim Total As Integer
    
    Range("C5").ClearContents
    
    intRow = Range("B6").End(xlDown).Row
    Range("C6:C" & intRow).ClearContents
    
    For i = 6 To intRow
    
       N = Range("B" & i) * Range("D5")
    
       Range("C" & i).Value = N
       Total = Total + N
       Range("C5").Value = Total
    
    Next
    
End Sub