what is on balance volume obv 
on balance volume obv is a technical trading momentum indicator that uses volume flow to predict changes in stock price joseph granville first developed the obv metric in the 1963 book granville s new key to stock market profits 1granville believed that volume was the key force behind markets and designed obv to project when major moves in the markets would occur based on volume changes in his book he described the predictions generated by obv as a spring being wound tightly he believed that when volume increases sharply without a significant change in the stock s price the price will eventually jump upward or fall downward image by sabrina jiang investopedia 2021formula for on balance volume obv 