Start: 100, increment: +10 (e.g. 110, 120), allow for future addition (e.g. 109, 115)

[Heezea]

I was wondering if it is possible to start a database table at 100, increment it by 10 (example: 100, 110, 120, ...) but still allow for future inclusion of non-10-incremented numbers (example: 109, 115) so I would end up with 100, 109, 110, 115, 120, ...

The reason I would like to do this is that various statements (example: insufficient bolt length) will be tied to each number (example: 110 - insufficient bolt length), and I want to establish routine of entering the data as 3-digit numbers. I expect that 100-990 will cover most of the range, but want to be able to add to the range if needed, without going into 4-digit numbers.

Initially, I tried entering the auto-increment number in Column A, and then a second column would take Column A * 10 + 100, but that doesn't allow me to include numbers such as 109 or start at 100.

[JoeM]

You really do not want to be using Autonumbers in this manner. They should not be used for anything other than to guarantee a unique identifier.
See: http://www.utteraccess.com/wiki/index.php/Autonumbers

If you want some sort of special counter, if you do not want to enter them manually, you will probably need to incorporate some VBA code to assign them. The logic would be something like looking up the Maximum value currently in the table, and adding 10 (and probably want to check that the hightest number is already a multiple of 10),