TextBox Updating

Private Sub CommandButton15_Click()
Sheets("Column Sort").Range("A2", "N3340") = ""
For a = 1 To 1000
b = Int(a / 10)
Sheets("Column Sort").Range("O1") = b
TextBox2 = Sheets("Column Sort").Range("O1")
Sheets("Column Sort").Range("A3340:N3340").Copy_ Destination:=Sheets("Column Sort").Range("A" & a)
Next a
End Sub

What I want is for TextBox2 to show the variable 'a' as a percentage done.
Although the macro works, it only updates TextBox2 when it has finished.
ie TextBox2 shows 100.
How can I get TextBox2 to update as it runs through the macro, which should show 1 thru to 100.

Am using Excel97 if it makes a difference.

I would do away with the text box - use

application.statusbar = "whatever you want as a string"

to update the message

when finished, application.statusbar=""

I see what your getting at but as all the rest of the data diplayed is on the UserForm I have created, I wanted the progress to be on the Form as well. (Looks nice)

Any ideas?

Try putting a DoEvents statement just before the NEXT statement - I've
just run some sample code at this end and it appears to work ok

The DoEvents did the trick nicely thankyou.