for the income statement that shows the contribution margin which come from sales minus variable production and selling costs. if compare with the percentage of contribution margin divide by sales will know which geographic got higher revenue. the following are percentage of contribution margin divide by sales united states 35%, canada 37% and mexico 31%. the percentage show the contribution margin that has highest is canada and lowest is mexico, so in canada should add the sales unit volume from mexico, so in canada should add the sales unit volume from mexico, as well as mexico should reduce the sales in unit volume but the contribution margin has to more than fixed cost.