The McClellan Volume Oscillator is calculated similarly to the McClellan Oscillator (see chart 1) except that advancing/declining volume is used instead of advancing/declining issues. A healthy bull market is accompanied by a large number of stocks making moderate upward advances in price. A weakening bull market is characterized by a small number of stocks making large advances in price, giving the false appearance that all is well. This type of divergence often signals an end to the bull market. A similar interpretation applies to market bottoms, where the market index continues to decline while fewer stocks are declining. The McClellan Volume Summation Index is a market breath indicator based on an accumulation of the McClellan Volume Oscillator (see above). The McClellan Volume Summation Index is a long-term version of the McClellan Volume Oscillator. Its interpretation is similar to that of the McClellan Volume Oscillator except that it is more suited to major trend reversals. Different than price files available elsewhere, MasterDATA's price files include total combined volume of all component issues (not the trade volume for the index or ETF itself). Typical volume oscillator lines can be plotted on a chart showing total component volume of the index or ETF. Additionally, Equivolume and candlevolume charts are possible reflecting total component volume, often a much better reflection of what is "really" going on in the index or ETF. Additionally, Custom Indicators developed for individual securities that require a volume value may be used with these files.
MetaStock can only display bar and candlestick charts utilizing price files in a specified format. The price files included with the MasterDATA Composite Plug-in allow such display utilizung total component volume rather than trading volume of the instrument itself (if any). | 
