Developed by Marc Chaikin, the Chaikin Money Flow oscillator is calculated from the daily readings of the Accumulation/Distribution Line. The basic premise behind the Accumulation Distribution Line is that the degree of buying or selling pressure can be determined by the location of the close relative to the high and low for the corresponding period (Closing Location Value). There is buying pressure when a stock closes in the upper half of a period's range and there is selling pressure when a stock closes in the lower half of the period's trading range. The Closing Location Value multiplied by volume forms the Accumulation/Distribution Value for each period.