He's calculated that it would take him two years to save up enough for a car.

calculated 是动词 calculate 的过去分词形式。calculate 的意思是"计算、估算"，calculated 在这里表示"经过计算得出的"。 calculate 来自拉丁语 calculus（小石子），古代人用小石子来计算数字，后来引申为"计算"的意思。