The weekly extended benefit amount payable to an individual for a week of total unemployment in his eligibility period shall be an amount equal to the weekly basic or augmented benefit amount, whichever is appropriate, payable to him during his applicable benefit year. For any individual who was paid benefits during the applicable benefit year in accordance with more than one weekly basic or augmented benefit amount, whichever is appropriate, the weekly extended benefit amount shall be the average of such weekly basic or augmented benefit amounts, whichever are appropriate.