what is a breadth indicator 
breadth indicators are mathematical formulas that measure the number of advancing and declining stocks and or their volume to calculate the participation in a stock index s price movements by evaluating how many stocks are increasing or decreasing in price and how much volume these stocks are trading breadth indicators help in confirming stock index price trends or can warn of impending price reversals calculating breadth indicatorsthere are a number of breadth indicators each with their own formula and method of calculation some breadth indicators are cumulative with each day s value added or subtracted from the prior value others are non cumulative with each day or period providing its own data point one of the simplest breath indicators is the advance decline line it s a cumulative indicator where net advances number of advancing stocks number of declining stocks is added or subtracted from the prior value 