# 指数移动平均线(EMA)

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## 指数移动平均线 (EMA)

• 第一个价格（MT4、汇图宝）
• 前 指数移动平均线(EMA) N 个价格的简单移动平均线 (Stockcharts)。

## EMA指数平滑移动平均

Exponential moving averages are recommended as the most reliable of the basic moving average types. They provide an element of weighting, with each preceding day given progressively less weighting. Exponential 指数移动平均线(EMA) smoothing avoids the problem encountered with simple moving averages, where the average has a tendency to "bark twice": once at the start of the moving average period and again in the opposite direction, at the end of the period. Exponential moving average slope is also easier to determine: the slope is always down when price closes below the moving average and always up when price is above.

## Formula

To calculate an exponential moving average (EMA):

• Take today's price multiplied by an EMA%.
• Add this to yesterday's EMA multiplied by (1 指数移动平均线(EMA) - EMA%).

If we recalculate the earlier table we see that the 指数移动平均线(EMA) exponential moving average presents a far smoother trend:

## Simple Moving Average Formula

To calculate a 5 day simple moving average ("SMA"), take the sum of the last 5 days prices and divide by 5.

 Day 1 2 3 4 5 6 7 8 9 Price (\$) 16 17 17 10 17 18 17 17 17 5 指数移动平均线(EMA) Day SMA 15.4 15.8 15.8 15.8 17.2