[VBA]Sub ZerosAndBlanks()
' Fill zero and blank cells
Dim cll As Range, rng As Range, rngB As Range
Set rng = Range(Cells(1, 3), Cells(Rows.Count, 3).End(xlUp))
Set rngB = rng.SpecialCells(xlCellTypeBlanks)
rng.Value = "out of composite"
rngB.Value = "in composite"

End Sub
[/VBA]