Box d control number all I have is 12

[dgrattanburl]

I had just the number 38, but it was for a W-2 that turbotax couldn't download.  I had to enter it manually.  This is a relatively small employer, so my hunch is that this is just a sequential number like an employee number.  I entered it but I don't think it mattered since I was doing that W-2 manually.