(4) Employment must be trade or business employment

An employee shall be treated as a qualified employee for any taxable year of the employer only if more than 50 percent of the wages paid or incurred by the employer to such employee during such taxable year are for services performed in a trade or business of the employer. Any determination as to whether the preceding sentence applies with respect to any employee for any taxable year shall be made without regard to subsection (e)(2).