979.8. The deduction contemplated in section 979.6 shall not exceed, where the market-maker works for his own account, the least of(a) $65,000;
(b) 50% of his profits for the particular period; or
(c) the amount by which the sum of $500,000 plus the aggregate of the amounts withdrawn by him from his reserve account for contingent losses within the particular period or a previous particular period and then included in computing his income exceeds the aggregate of the deductions he is allowed to make under section 979.6 for the previous taxation years.