The MACD is implemented as a composite function. The expression is:

SUB(EMA(values;12); EMA(values;26))

The Moving Average Convergence Divergence (MACD) is a trend following momentum indicator that shows the relationship between two moving averages of prices. It is calculated by subtracting the value of a 26-day exponential moving average from a 12-day exponential moving average. The MACD proves most effective in wide-swinging trading markets.

In a market which is accelerating upwards, the short moving average will rise faster than the longer moving average. This will lead to a rising MACD.

In a market which is accelerating downwards, the short moving average will fall faster than the longer moving average. This will lead to a falling MACD.

The MACD was developed by Gerald Appel.