The McClellan Oscillator uses advancing issues and declining issues on the New York Stock Exchange (NYSE) to gauge market breadth. The components are:

1. Advancing Issues - Declining Issues
2. Calculate both the 19 & 39-day exponential moving average (EMA) of [Advancing Issues - Declining Issues]
3. Plot the result of the 19-day EMA minus the 39-day EMA

The McClellan Oscillator is shown next on the chart of the Nasdaq 100 QQQQ's:

Just like the MACD, when the short-term moving average crosses above the longer term moving average, the plotted line crosses the zero line. Therefore, when the McClellan Oscillator crosses above zero, the trend of the advance-decline issues is positive = bullish sign. In contrast, when the McClellan Oscillator crosses below zero, the trend of the advance-decline issues is negative = bearish sign.

Generally, above +70 is considered an overbought condition and below -70 is an oversold condition.

McClellan Oversold Buy Signal

When the McClellan Oscillator crosses above the -70 oversold line.

McClellan Overbought Sell Signal

When the McClellan Oscillator crosses below the +70 overbought line.

The McClellan Oscillator takes market breadth data and creates an easy to use technical indicator that generates clear buy and sell signals.