A situation in which the price or rate of a security does not change between two periods. This can be over any time frame including a trading day, week, or even as much as a year. Sometimes seen as "UNCH." Taobiz explains Unchanged For example, assume that the closing price of ABC stock on Tuesday was $13.50 and on Wednesday the price also closed at $13.50. During this period, the price of ABC stock is referred to as being unchanged, even though the price of the stock likely fluctuated during the day.