Relative Strength

The Relative Strength Index (RSI) is a financial technical analysis oscillator showing price strength by comparing upward and downward close-to-close movements.The RSI is popular because it is relatively easy to interpret. It was developed by J. Welles Wilder and published in Commodities magazine (now called Futures magazine) in June 1978, and in his New Concepts in Technical Trading Systems the same year.Note that the term relative strength also refers to the strength of a security in relation to the overall market or to its sector. For instance XYZ might rise 2% when the rest of the market rises 1%. This is sometimes called relative strength comparative to avoid confusion. It's unrelated to the Relative Strength Index described here.
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A stock's price movement over the past year as compared to a market index (like the S&P 500). Value below 1.0 means the stock shows relative weakness in price movement (underperformed the market); a value above 1.0 means the stock shows relative strength over the 1-year period. Equation for Relative Strength: [current stock price/year-ago stock price] divided by [current S&P 500/year-ago S&P 500]. Note this is a potentially misleading indicator of performance because it does not take risk into account.

Price performance of a stock divided by the price performance of an appropriate index over the same time period. A measure of price trend that indicates how a stock is performing relative to other stocks.