Inserting fixed value with form


I have a simple form, where user should enter a few data on first visit, like date, company name, job description…
So, how can I insert a certain value (eg. letter “a”) in one column w/o that the one who is inserting this data would even know.
Description: Someone is inserting a job listing via form and obviously the opening is active (a), but latter on this would be closed (c), or postponed (p)… so first value, first time data is entered, should be “a”, but I don’t want that user would even bother with this (yes, could be a field with only one option to select… but as said, I don’t want user to bother with this)?