[经] variance from planned cost of materials

cái liào jì huà chéng běn chā yì ㄘㄞˊ ㄌㄧㄠˋ ㄐㄧˋ ㄏㄨㄚˋ ㄔㄥˊ ㄅㄣˇ ㄔㄚ ㄧˋ