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Follow Line

Follow Line is a common MT4 FX indicator based on trend following.

The main idea behind the calculation is volatility:
-Indicator Line increases as price goes above Bollinger Bands but with 1 standard deviation.
-Likewise when price moves below the lower Bollinger Band with 1 Standard deviation, Follow -Line decreases down.
-As you can imagine, indicator stays as a flat line when price moves between the bands.

There are two critical settings about the indicator:

1- Bollinger Bands Deviation is set to 1 as default but if you want to have early signals you have to decrease that amount. Also you'd better increase that to have flat values on sideways market conditions for not getting chopped by the early but false signals.

2- ATR Filter is activated in default settings and the indicator follows the trend with a distance from Highs and Lows considering ATR (default length 5) values. If you turn off the ATR filter, the indicator line only takes into account the Highs and the Lows. Indicator will get more agile but the risk of choppy signals can be taken that time. I personally advise you to increase the Bollinger Band Deviation from 1 to between 1.5-2 to stabilize the fake signals when ATR filter is turned off.

Signals can be shown on the graph:

BUY: when Follow Line changes direction from red to blue.(which means Price is above Bollinger Upper Band with 1 standard deviation)
SELL: when Follow Line changes direction from blue to red. (which means Price moves below Bollinger Lower Band with 1 standard deviation)

Finally, some of you may know there are also several Follow Line indicators on TradingView but unfortunately they don't show the same exact values (close but not same) comparing with original version of MT4 and the Metastock version that I've coded recently. So, I shared this stuff to have the exact same values on graphs on all platforms.