The Department shall prepare and conduct examinations as often as necessary, but at least once a year if there are any applicants. A candidate who failed a subject that is part of the examination given may be reexamined in that subject only at any subsequent examination held within 1 year of the date the candidate took the initial examination, and if the candidate passes that subject the candidate is considered to have passed the examination. The Department, however, may decide to reexamine an unsuccessful candidate in every subject.