You could put this in B4 (or any column, row 4) and drag down
=IF(MOD(ROW($A4),4)=0,AVERAGE($A1:$A4),"")
Or you could put this macro into the worksheet's module. It puts answers in column C
Code:
Sub AvEvery4Rows()
Dim rng As Range 'range to work with
Dim cel As Range 'individual cells within that range
Dim Tally As Double 'total of the 4 rows being averaged
Dim i As Integer 'incrementer, will be 0 to 1 less than number of rows
Set rng = Range("A1:A" & Cells(Rows.Count, "A").End(xlUp).Row)
For Each cel In rng
If cel.Row Mod 4 = 0 Then
For i = 0 To 3
Tally = Tally + cel.Offset(-i, 0).Value
Next i
cel.Offset(0, 2).Value = Tally / 4
i = 0
Tally = 0
End If
Next cel
End Sub
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