Developed by Larry Williams, Williams %R is a momentum indicator similar to the Stochastic Oscillator. Typically used to determine overbought and oversold levels in nontrending markets. The scale ranges from 0 to -100 with readings below -20 considered overbought, and readings above -80 considered oversold. Williams %R is normally calculated using 14 day periods, but can also be used over different time frames.
Chart courtesy of Prophet Financial Systems