This indicator is based on the fact that the closing price is usually higher, than the opening price in the bullish market. The situation is opposite in the bearish market. As a result, the movement vigor is determined by the situation, when the price is at the end of the period. Calculation RVI = (Close-open)/(high-low) This indicator doesn't have overbought/oversold areas (this helps the beginners not to become confused, but, at the same time, it is not clear how to use this indicator). Books about Forex market advise to place these areas by yourself, but this leads to different assessments and misrepresentation. I do not recommend to use this indicator.