The contribution margin approach uses the product ' s unit con ? tribution margin of its contribution margin ratio , which give the increase in operating income for each additional unit sold or for each dollar of sales revenue , respectively 邊際貢獻法使用產(chǎn)品的單位邊際貢獻或他的邊際貢獻率,即銷售量或銷售額每增加一個單位時邊際貢獻的增長幅度。