In
technical analysis, a line plotting the
advance-decline index over a period of time. The advance-decline index takes the total of
stock issues increasing on a
trading day and subtracts the number of stock issues declining on the same day. Technical analysts use the index as an
indicator of market movements, and use the advance-decline line to confirm a movement. If the line slopes upward over time, it indicates an upward
trend, and, if it slopes downward, the opposite is true.