This is as much a specific DAO suggestion as a general design and query suggestion that affects all aspects of your application. The Microsoft Access default for number is to use Double. While this has the greatest range and floating point accuracy of all the numeric types, it is also the most expensive to store, convert, and compute. If your numbers are of limited range or always integral values, you should consider changing your column data types to suit. This will make DAO fetch and retrieval code marginally faster due to fewer bytes being retrieved but will have a significant effect on numerical calculations (as integers are used in place of floating point values).
Tip #22 has similar information regarding text versus memo data types.