[经] fixed percentage of diminishing value method
dìng lù jià zhí dì jiǎn fǎ ㄉㄧㄥˋ ㄌㄨˋ ㄐㄧㄚˋ ㄓˊ ㄉㄧˋ ㄐㄧㄢˇ ㄈㄚˇ