Modules & VBA :: DAO To Update Table Recordset - Increment

I have inherited an old database with a new field to add some new invoice numbers and increment the number to each recordset by + 1. Starting at 001. I have formatted the field to a Number Field and formatted it to 000"/2015". I now need to populate over 2000 records with the sequential numbers for each record.

I have created the following code as my attempt. Of course it doesn't work!

Code:
Sub AddNumbertoRecords()
Dim db As DAO.Database
Dim rst As DAO.Recordset
Dim counter As Long
counter = 1
Set db = CurrentDb()

[Code] ....