What is the current state of the law on "aberrant behavior"?

The government concedes that aberrant behavior is recognized as a mitigating circumstance which may be used as a basis for downward departure. We have taken an especially broad view of the type of behavior that might be considered "aberrant" under the guidelines, recognizing that there is an "aberrant behavior spectrum" in terms of which aberrant behavior is to be determined. Compare United States v. Takai, 941 F.2d 738, 743-44 (9th Cir.1991) (two crimes of conspiracy and offering money sufficiently related to make it a single act of aberrant behavior) with United States v. Carey, 895 F.2d 318, 325 (7th Cir.1990) (check-kiting scheme spanning 15-month period not aberrant behavior).