The value of the allotment which State agencies shall be authorized to issue to any households certified as eligible to participate in the food stamp program shall be equal to the cost to such households of the thrifty food plan reduced by an amount equal to 30 per centum of the household’s income, as determined in accordance with section
2014
(d) and (e) of this title, rounded to the nearest lower whole dollar: Provided, That for households of one and two persons the minimum allotment shall be $10 per month.