MACD, which stands for Moving Average Convergence Divergence, is a trend-following momentum indicator that shows the relationship between two moving averages of prices. Developed by Gerald Appel, MACD is one of the simplest and most reliable indicators available. This tool is used to identify moving average which indicate a new trend, regardless of whether it is bullish or bearish. After all, the most important priority in trading is to find a trend, because the most money revolves around it.
The most popular formula for the "standard" MACD is the difference between 26-day and 12-day Exponential Moving Averages (EMAs). This is the formula that is used in many popular technical analysis programs and quoted in most technical analysis books. Using shorter moving averages will produce a quicker, more responsive indicator, while using longer moving averages will produce a slower indicator, less prone to whipsaws.
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Very lame indicator.
This is a very lagging indicator that fails miserably in back-testings. I advise you to focus on charts and price action, rather than indicators that showing you nothing but the past.