Inspired by the prior work of Joe Granville and Larry Williams, Marc Chaikin developed a new volume indicator, extending the work done by his predecessors. The Chaikin Oscillator is a moving average oscillator based on the Accumulation/Distribution indicator.

The most important signal generated by the Chaikin Oscillator occurs when prices reach a new high or new low for a swing, particularly at an overbought or oversold level, and the oscillator fails to exceed its previous extreme reading and then reverses direction.
Signals in the direction of the intermediate-term trend are more reliable than those against the trend. A confirmed high or low does not imply any further price action in that direction.
A second way to use the Chaikin Oscillator is to view a change of direction in the oscillator as a buy or sell signal, but only in the direction of the trend. For example, if we say that a stock that is above its 90-day moving average of price is in an up-trend, then an upturn of the oscillator while in negative territory would constitute a buy signal only if the stock were above its 90-day moving average--not below it. A downturn of the oscillator while in positive territory (above zero) would be a sell signal if the stock were below its 90-day moving average of closing prices."

This indicator is described in more details in the Steve Achelis' book "Technical Analysis from A to Z".

Formula: