[经] method of calculating depreciation

zhé jiù fèi jì suàn fāng fǎ ㄓㄜˊ ㄐㄧㄡˋ ㄈㄟˋ ㄐㄧˋ ㄙㄨㄢˋ ㄈㄤ ㄈㄚˇ