How to Change values by increment in Data Table

Here is a generic way to do this. I haven't looked at your file.

Sub x()

Dim nMin As Long, nMax As Long, nStep As Long

nMin = Application.InputBox("Enter min", Type:=1)
nMax = Application.InputBox("Enter max", Type:=1)
nStep = Application.InputBox("Enter increment", Type:=1)

With Cells(1, 1)
    .Value = nMin
    .DataSeries Rowcol:=xlColumns, Type:=xlLinear, Date:=xlDay, _
        Step:=nStep, Stop:=nMax, Trend:=False
End With

End Sub