Hi, all

Can someone explain to me why this code doesn't work? I get a 424 error and
the debugger points to the line I indicate below:

Sub volatility()
Sheets("HistoricalVolatility").Select
z = 2 + 1
vol = 0
Count = 0
Do While Cells(z, 7) < ""
vol = vol + Log(Cells(z, 7).Value) / Log(cell.Offset(-1, 0).Value) '
here's the prob
Count = Count + 1
z = z + 1
vol = vol / Count
Loop
Sheets("Options").Range("B9").Value = vol
End Sub