The volume accumulation oscillator is a modified on balance volume (OBV) study. The volume accumulation oscillator assigns a proportional amount of volume to the mean price for a period, depending on where the close falls in relation to the mean price. All volume is assigned to buying or selling only if the close is the high or the low for a period. Formula: Where: VAO = current volume accumulation C = close H = high L = low V = volume see, John J. Murphy, Technical Analysis of the Futures Markets, A Comprehensive Guide to Trading Methods and Applications, New York: New York Institute of Finance, A Prentice-Hall Company, 1986, pp. 188-193.Volume Accumulation Oscillator