McClellan Summation Index
McClellan Summation Index
Oscillator = (19-day EMA of securities advancing - securities declining) - (39-day EMA of securities advancing - securities declining) + Previous day's McClellan Summation Index.
The importance of the McClellan Summation Index comes from the fact that price averages may be driven by only a few securities. That is, a few securities may be making large gains while the rest of the securities on the NYSE are posting losses, or vice versa. A price average, then, may not reflect the true conditions of the market. The McClellan Summation Index attempts to control for this.