The $1,944 difference between the actual factory overhead of $20,900 incurred during January and the applied amount of $18,956 represents underapplied factory overhead. If amount of underapplied or overapplied overhead at the end of the year is small relative to other production cost, it would be charged to Cost of Goods Sold. If the amount is large, it must be allocated between ending inventories and Cost of Goods Sold for external reporting purposes. The significance and disposition of underapplied and overapplied overhead are discussed in detail in Chapter 11.