hi there...
u can't do this without updating the macro...
LastRowA = Range("A7").End(xlDown).Row - 4 ' -4 Cos' formula is in Row 4
the code above identifies the row no. as when you select Cell A7 & hit control-shift-down arrow in Excel. you have to less 4 rows from that cos your formula in cell "b4" is using referencing relative from row 4.
this will show the right no. each time your set changes.
Secondly, selecting cells is redundant. so i have removed all select codes. You will pick that up as you get along 
lastly, if you need it left justified (aligned?)....
This is what will be generated if you use the macro recorder...
With Selection
.HorizontalAlignment = xlGeneral
.VerticalAlignment = xlCenter
.WrapText = False
.Orientation = 0
.AddIndent = False
.IndentLevel = 0
.ShrinkToFit = False
.ReadingOrder = xlContext
.MergeCells = False
End With
tweak it like this:
Range("A1").HorizontalAlignment = xlGeneral
hope i have been clear with the explanation....
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