Volume points to the amount of a financial instrument that was traded over a specified period of time. It can refer to shares, contracts or lots. The data is tracked and provided by market exchanges. It is one of the oldest and most popular indicators and is usually plotted in colored columns, green for up volume and red for down volume, with a moving average. It is one of the few indicators that is not based on price. High volume points to a high interest in an instrument at its current price and vice versa.