[UNPUBLISHED]

James E. Caldwell challenges the sentence of four concurrent terms of 100 *540 months in prison that the district court 1 imposed after he pleaded guilty to four counts of crack cocaine distribution in violation of 21 U.S.C. § 841(a)(1) and (b)(1)(B). Caldwell argues on appeal that the sentence was unreasonable because the district court erroneously concluded that it lacked discretion to vary below the advisory Guidelines range based on the sentencing differential between crack and powder cocaine offenses, and because the Sentencing Commission’s criticism of the differential in its reports concerning federal cocaine sentencing policy constitutes a mitigating factor that the court should have considered pursuant to 18 U.S.C. § 3553(a).

A sentence within the advisory Guidelines range is presumptively reasonable. See United States v. Lincoln, 413 F.3d 716, 717 (8th Cir.), cert. denied, — U.S.-, 126 S.Ct. 840, 163 L.Ed.2d 715 (2005). The record indicates that the district court considered the disparate penalties for crack offenses and the Sentencing Commission’s reports to the extent permitted by our holding in United States v. Spears, 469 F.3d 1166 (8th Cir. 2006) (en banc). Caldwell has not identified any section 3553(a) factor that the district court improperly weighed or irrelevant factor upon which the court unduly relied. See United States v. Haack, 403 F.3d 997, 1004 (8th Cir. 2005). We find no abuse of discretion and conclude that Caldwell’s sentence is reasonable. See id. at 1003-04.

Accordingly, the judgment is affirmed.