MCL 208.1201 provides for a series of specific adjustments that must be made to business income to arrive at the business income tax base. One of these adjustments is a deduction for self employment income as defined in section 1402 of the Internal Revenue Code. MCL 208.1201(2)(h). Under section 1402, the business income of an individual or sole proprietor, and a partner's distributive share of partnership income, whether distributed or not, from any trade or business carried on by the partnership, may be considered self employment income (with certain statutory exceptions), and subject to the federal self employment tax. Therefore, a sole proprietorship or partnership may deduct any income subject to the federal self employment tax when computing the MBT income tax base. Corporations, including S corporations, are not subject to self employment tax, and, as a result, no deduction is allowed for earnings from self employment income for corporate entities. There is no deduction allowed for S corporation distributions that is equivalent to the self employment deduction allowed for partnerships and sole proprietorships under the MBT.