Another tool I have used for many years is the Relative Strength Index (RSI), which was developed by Welles Wilder.

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Many of the indicators I have used for years, such as Gerry Appell's MACD and Welles Wilder's RSI, have subsequently gained wide popularity.

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That is the same reason that I try to give Joe Granville credit in my articles about on balance volume or Welles Wilder when I talk about the RSI or ADX.

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