⁷The case of CARA utility with only labor income risk is included here because Carroll and Kimball (1996) show that it is a knife-edge case that is unrepresentative of the broader effects of uncertainty (notably, it fails to exhibit the consumption concavity that holds for virtually every other combination of assumptions); indeed, the addition of rate-of-return risk renders the optimal consumption function concave even under CARA utility. (The other traditional objection is that the optimal consumption plan under CARA utility generally involves setting consumption to a negative value in some states of the world; it is hard to think of a plausible economic interpretation of negative consumption.)