Swing Index   

The Swing Index (Wilder) is a popular indicator that shows comparative price strength within a single instrument by comparing the current open, high, low and close prices with previous prices. This momentum indicator is used primarily as a component of the Accumulative Swing Index. The Swing Index alone doesn’t provide much in the way of signals. It should be used in conjunction with the Accumulative Swing Index
It provides an indication of the real strength and direction of a price trend by providing a single indicator line, which can be analyzed for support and resistance lines.