A constrained efficient annuity pair. This figure illustrates a constrained efficient pair of contracts (AL, AH) solving Eq. (1). AH lies above AH*, the full insurance actuarially fair contract for high-risk types. Hence, (AL, AH) involves redistribution from low to high-risk types. Since the low-risk (high-risk) types’ indirect utility VL is lower (higher) with AL (AH) than with AL* (AH *), low-risk (high-risk) types are worse (better) off with (AL, AH) than they are with the pair of individually fair full insurance contracts (AL*, AH*). When type is observable, (AL, AH) is also inefficient (in the sense of Eq. (14)) because each type could be made equally well off with the contract pair (A′L, AH) at a lower expected cost to firms; the distance between A′L and ĀL (the full insurance contract with the same actuarial cost for the low-risk type as AL) is a measure of this inefficiency.