 By contrast, the base for a theoretically correct Schanz–Haig–Simons (SHS) income tax is each individual's annual consumption plus current additions to savings.Thus current receipts that are otherwise taxable remain in the tax base, even if they are saved, and withdrawals from earlier savings are not currently taxed since they were assessed in a prior year.Stated differently, the SHS tax base has two components—current consumption and current savings (including current appreciation accruing to earlier investments)—whereas a cash-flow consumption tax has only a single component—current consumption.