 In spite of their differences, however, both a cash-flow consumption tax and an SHS tax require that dollars paid out as business or investment expenses be eliminated from the base.This is necessary under a cash-flow consumption tax because business and investment expenses are not consumption and it is necessary under an SHS tax because these expenditures are neither consumption nor additions to savings.Since business and investment outlays have no place in the base of either tax, intuition suggests that business and investment interest expenses would be treated identically under a cash-flow consumption tax and an SHS tax.