Assuming that your Data is in Column B and your bounds are in C15 and C16
Sub PasteAFormula()
Dim strFormulaToPaste As String
strFormulaToPaste = "B" & Range("C15").Value & ":B" & Range("C16").Value
strFormulaToPaste = "=STDEV.S(" & strFormulaToPaste & ")"
MsgBox strFormulaToPaste
End Sub
You can then put the contents of strFormulaToPaste into a cell.