(1) "Base period" means the first four (4) of the last five (5) completed calendar quarters immediately preceding the beginning of a benefit year. If a claimant has insufficient wages in the base period to establish eligibility for unemployment benefits, the "base period" shall be the last four (4) completed calendar quarters immediately preceding the beginning of a benefit year.
(2)  "Alternate base period" means the first four (4) of the last five (5) completed calendar quarters immediately prior to the Sunday of the week in which a medically verifiable temporary total disability occurred. If a claimant has insufficient wages in the base period to establish eligibility for unemployment benefits, the "alternate base period" shall be the last four (4) completed calendar quarters immediately prior to the Sunday of the week in which a medically verifiable temporary total disability occurred. To use the alternate base period, a claimant must file within three (3) years of the beginning of the temporary total disability, and no longer than six (6) months after the end of the temporary total disability.