This indicator is calculated by dividing the weekly upside and downside volumes by the weekly total volume. If prices move steadily upward (strong uptrend) with strong volume, this indicates that buyers are accumulating shares. A healthy market should be supported by strong up volume. If not there is a negative divergence between the market and breadth. This could happen, if only heavy weighted stocks in an index are pushing the market higher but the majority of small weighted stocks are already being sold by investors. By separating the up volume from the down volume, investors can get an insight about the future direction of the given index or market. Divergences between the market and volume should be monitored closely as a trend reversal could be ahead!
Bullish: Upside volume above downside volume
Bearish: Upside volume below downside volume
Watch out for divergences between the market and advancing issues