(a) In generalFor purposes of section 38, in the case of an eligible employer, the retirement auto-enrollment credit determined under this section for any taxable year is an amount equal to—
(b) Credit periodFor purposes of subsection (a)—
(1) In general
The credit period with respect to any eligible employer is the 3-taxable-year period beginning with the first taxable year for which the employer includes an eligible automatic contribution arrangement (as defined in section 414(w)(3)) in a qualified employer plan (as defined in section 4972(d)) sponsored by the employer.
(c) Eligible employer
For purposes of this section, the term “eligible employer” has the meaning given such term in section 408(p)(2)(C)(i).