(a) You must keep records for 5 years in a form suitable and readily available for expeditious review, as specified in § 63.10(b)(1).

(b) You must keep each record on site for at least 2 years, as specified in § 63.10(b)(1). You can keep the records off site for the remaining 3 years. Records may be maintained in hard copy or computer-readable format including, but not limited to, on paper, microfilm, hard disk drive, floppy disk, compact disk, magnetic tape or microfiche.