MEMORANDUM *

Alan C. Cone appeals his conviction and sentence for fraud involving his Medicare and Medicaid billing practices. See 18 U.S.C. §§ 287, 371, 1001, 1341, 1343. We affirm.

(1) Cone contends that the evidence was not sufficient to support the verdict. We disagree. We have reviewed the record, and it is clear that a rational trier of fact could find the elements of the crimes beyond a reasonable doubt. See United States v. Paeheco-Medina, 212 F.3d 1162, 1163 (9th Cir. 2000). The fact that much of the evidence was supplied by an accomplice does not affect our conelusion. See United States v. Necoechea, 986 F.2d 1273, 1282 (9th Cir. 1993).

(2) Cone challenges his sentence because the district court determined the amount of the government’s loss when it calculated the guideline sentence. That determination was required by the Guidelines, U.S.S.G. § 2Fl.l(b)(l) (1998), but Cone claims that the Constitution was thereby violated. See Apprendi v. New Jersey, 530 U.S. 466, 490, 120 S.Ct. 2348, 2362-63, 147 L.Ed.2d 435 (2000). Again, we disagree. Apprendi only applies to “increases [in] the penalty for a crime beyond the prescribed statutory maximum.” Id. It does not apply to guideline calculations which increase the penalty within that maximum. See United States v. Hemandez-Guardado, 228 F.3d 1017, 1027 (9th Cir. 2000); see also United States v. Sullivan, 255 F.3d 1256, 1264-65 (10th Cir. 2001); United States v. Pratt, 239 F.3d 640, 648 (4th Cir. 2001).

(3) Finally, Cone asks us to determine whether his counsel was ineffective. We decline to do so. That is an issue which is generally left for determination in a 28 U.S.C. § 2255 proceeding. See United States v. Quintero-Barraza, 78 F.3d 1344, 1347 (9th Cir. 1995); United States v. Laughlin, 933 F.2d 786, 788 (9th Cir. 1991). Nothing in the undeveloped record before us suggests that we should deviate from the general rule. See United States v. Davis, 36 F.3d 1424, 1433 (9th Cir. 1994).

AFFIRMED.