Double-entry bookkeeping implies that: profits cannot be negative because profit equals the value of final output less costs. profits fill the gap between the sum of employee compensation, rents and interest on the one hand and the value of final output on the other hand. aggregate income net of profits is less than the value of final output because profit can add or take away from final output. aggregate income net of profits is greater than the value of final output because profit can add or take away from final output.