; and (B) a discussion of the methodology used to prepare, and the basis for, each such estimate; and (2) a comparison of the estimate of costs described in paragraph (1) with any available estimates of costs made by such committee or by any agency. (b) Look-Back reviews CBO shall periodically submit to Congress a report, prepared in consultation with the Chairman of the Administrative Conference of the United States, that— (1) reviews a sample of laws of a public character for which an estimate was prepared under subsection (a)(1)